What do Quadratic Selection sort, and Shell sort have in common?
They both used a/an_______based implementation in the standard form and are both relatively_____to the order of the data. The main similarity is that each one creates an environment in which a_____strategy works more efficiently.
1. blank
2. linked list
3. array
4. hybrid
5. tree
6. sensitive
7. insensitive
8. complex
9. modern
10. simple
11. retrograde
12. advanced

Complete Question:

The first electric, general-purpose computer, ENIAC, was programmed by?

Group of answer choices.

A. Calculating algorithms on paper.

B. Entering code directly into the computer.

C. Flipping switches by hand.

D. Using MS-DOS as the operating system.

Answer:

C. Flipping switches by hand.

Explanation:

The first electric, general-purpose computer, ENIAC, was programmed by flipping switches by hand.

ENIAC is an acronym for Electronic Numerical Integrator and Computer, it was developed in 1945 by John Mauchly and J. Presber Eckert. ENIAC was used for solving numerical problems or calculation-related tasks by the process of reprogramming.

In order to give the ENIAC a series of machine instructions to follow in the execution of a task, the programmers had to undergo the cumbersome procedure of connecting, removing, reconnecting cables and flipping switches by hand because data couldn't be stored in memory.

Answer:

Lack of tone of voice

Explanation:

Remember, online disinhibition refers to the tendency of people to feel open in communication via the internet than on face to face conversations.

A lack of tone voice isn't categorized as a direct cause of online disinhibition because an individual can actually express himself using his tone of voice online. However, online disinhibition is caused by people's desire to be anonymous; their use of smartphones, and a lack of nonverbal cues.

Answer:

Explanation:

Skill acquisition improves quality, competence and competitiveness of an individual, It boost the chances of success and ability to make an impact. Access to information plays a verybhuge role in the society as it enables hearers to get updated while those who aren't informed are left behind. Some of the key competences or skills required in the information society include:

Critical thinking : Problem identification and ways to solve them.

Information sourcing and gathering : knowing where to get vital informations and facts

Effective communication, creativity, leadership, social, media and technological skills and so on.

The skills could be can be applied on schools in the form of :

Creating clubs such as the writing and debate clubs where students are given a research topic to write and present, this improves their research ability and communication skill.

Group project or assignment improves collaboration between members.

Assignments or projects requiring technology : Students may be given problems to solve with the use of computers moutwr programs and technology, this will help mad improve productivity.

Reward for innovation: Students should be paused mad encouraged for being creative, this will improve such individual and push others as well.

Answer:

Explanation: Research has proven that ;

The memory cell is also known as the  fundamental building block of computer memory.

It stores one bit of binary information and it must be set to store a logic 1 (high voltage level) and reset to store a logic 0 (low voltage level).

Answer:

A) Number of bits for byte = 6 bits

B) number of bits for index = 17 bits

C) number of bits for tag = 15 bits

Explanation:

Given data :

cache size = 64 kB

block size = 32 -byte

block address = 32 -bit

number of blocks in cache memory  

cache size / block size = 64 kb / 32 b = 2^11 hence the number of blocks in cache memory = 11 bits = block offset

A) Number of bits for byte

[tex]log _{2} (6)^2[/tex] = 6  bits

B) number of bits for index

block offset + byte number

= 11 + 6 = 17 bits

c ) number of bits for tag

= 32 - number of bits for index

= 32 - 17 = 15 bits

Answer:

Hash function have less collision than a internet checksum because of computational infeasibility.

Explanation:

A collision means there is more then one way to produce the same sum. It is nearly difficult to developed two messages with same hash however, in checksum, it is more easier to develop or modify two messages to have same sum, thereby enabling attackers to have access to the message or the information arising to less message integrity.

Answer:

space management and buffering speed.

Explanation:

There are different types of file management systems in a computer system, examples of which are NTFS, FAT, WAFL, etc, and are governed by protocols like NFS, TFTP, FTP, etc.

These file systems are used in storages like the hard disk drive, CD and DVD, solid-state drive, etc, to organize or manage the files from boot setup, device drivers to permission-seasoned user files.

Files in storage range from small to large files, for which the schema of the file system must adjust to manage and allocate free space to other files in the future. The file system is also able to index the location of a file for retrieval to a cache memory, making buffering faster.

Answer:

A. True

Explanation:

The correct option is A. True.

Actually, in using cloud infrastructures, the client necessarily cedes control to the CP on a number of issues which may affect security. It may have to restrict port scans and even penetration testing. Moreover, the service level agreements may not actually guarantee commitment to offer such services on the part of the CP. This may result in leaving a gap in security defenses.

Also, when the control of the CP changes, it's evident that the terms and conditions of their services may also change which may affect security.

Answer:

A. True

Explanation:

In FMS service routines, access controls are enforced automatically

and they that access and manipulate files and directories. Files and directories are usually accessed via access controls in most of the FMSs.

Additional processing overhead are usually imposed by FMS. Also, the FMS tend to restrict and hinder one from accessing secondary storage.

Answer:

Here is the Python program:

def scores(file):  # method scores that takes a file name as parameter and returns the sum and average of scores in a file

   with open(file, 'r') as infile:  # open the file in read mode

       lines = [score.split() for score in infile]  # split the scores into a list

       print("The scores are:",lines)  #print the scores

       for line in lines:  # loops through each score

           total= sum(int(score) for score in line)  # adds the scores

           average =total/len(line) # computes average by taking sum of scores and dividing by number of scores in file

       print("The sum is:", total)  #prints the sum of scores

       print("The average is:", "{:.2f}".format(average))   #prints the average

filename = input("Enter name of the file: ")  #prompts user to enter name of file

scores(filename) #calls scores method by passing the file name to it in order to compute sum and average of file contents i.e. scores

Explanation:

It is assumed that the scores in the file are separated by a blank space.

The scores() method takes a file name as parameter. Then it opens that input file in read mode using object infile.

split() method is used to split the scores in a file into a list. Suppose the scores are 1 2 3 4 5 6 . So after the split, they become ['1', '2', '3', '4', '5', '6']  

The loop iterates through each score in the file, splits them into a list and stores this list in lines. The next print statement prints these scores in a list.

The second loop for line in lines iterates through each score of the list and the statements: total= sum(int(score) for score in line)  and average =total/len(line) computes the total and average of scores.

total= sum(int(score) for score in line)  statement works as follows:

for loop iterates through each element of list i.e. each score

int() converts that string element into integer.

sum() method adds the integers to compute their total.

So if we have  ['1', '2', '3', '4', '5', '6']  each element i.e. 1,2,3,4,5,6 is converted to integer by int() and then added together by sum method. So this becomes 1+2+3+4+5+6 = 21. This result is stored in total. Hence

total = 21.

average = total/len(line) works as follows:

The computed sum of scores stored in total is divided by the number of scores. The number of scores is computed by using len() method which returns the length of the line list. So len() returns 6. Hence

average = total/len(line)

              = 21 / 6

average = 3.5

The next two print statement prints the value of sum and average and "{:.2f}".format(average)) prints the value of average up to 2 decimal places.

The screenshot of the program along with its output is attached.

Answer:

The Ampersand Symbol (Option B)

Explanation:

A 'address of operator' specifies that a given value that is read needs to be stored at the address of 'x'.

The address operator is represented by the ampersand symbol. ( & )

Hope this helps.

Answer:

struct PatientData{

   int heightInches, weightPounds;

};

Explanation:

In order to declare the required struct in the question, you need to type the keyword struct, then the name of the struct - PatientData, opening curly brace, data members - int heightInches, weightPounds;, closing curly brace and a semicolon at the end.

Note that since the object - lunaLovegood, is declared in the main function, we do not need to declare it in the struct. However, if it was not declared in the main, then we would need to write lunaLovegood between the closing curly brace and the semicolon.

Answer:

import csv

import sys

file_csv = argv

with open( "file_csv", "rb" ) as file:

      rowlist= csv.DictReader( file )

      dict_count={ }

      for row in rowlist:

           dict_count[ row[ 'department' ] ] = dict_count.get( row[ 'department' ], 0 ) + 1

      print( " The count of employees per department are", dict_count )

Explanation:

The python script in the solution above is able to accept user input csv files via command prompt and get an output of the number of employees for each department.

Explanation:

Refactoring consists of improving the internal structure of an existing program's source code, while preserving its external behavior. 

Answer:

In dynamic scoping the current block is searched by the compiler and then all calling functions consecutively e.g. if a function a() calls a separately defined function b() then b() does have access to the local variables of a(). The visible variables with the name of the function in which it was defined are given below.

Explanation:

In main() function three integer type variables are declared: a,b,c

In fun1() three int type variables are declared/defined: b,c,d

In fun2() three int type variables are declared/defined: c,d,e

In fun3() three int type variables are declared/defined: d,e,f

a. Main calls fun1; fun1 calls fun2; fun2 calls fun3

Here the main() calls fun1() which calls fun2() and fun2() calls func3() . This means first the func3() executes, then fun2(), then fun1() and last main()

Visible Variable:  d, e, f        Defined in: fun3

Visible Variable: c                 Defined in: fun2 (the variables d and e of fun2  

                                                                                                     are not visible)

Visible Variable: b                  Defined in: fun1 ( c and d of func1 are hidden)

Visible Variable: a                 Defined in: main (b,c are hidden)

b. Main calls fun1; fun1 calls fun3

Here the main() calls fun1, fun1 calls fun3. This means the body of fun3 executes first, then of fun1 and then in last, of main()

Visible Variable: d, e, f           Defined in: fun3

Visible Variable:  b, c              Defined in: fun1 (d not visible)

Visible Variable:  a                  Defined in: main ( b and c not visible)

c. Main calls fun2; fun2 calls fun3; fun3 calls fun1

Here the main() calls fun2, fun2 calls fun3 and fun3 calls fun1. This means the body of fun1 executes first, then of fun3, then fun2 and in last, of main()

Visible Variable:  b, c, d        Defined in: fun1

Visible Variable:  e, f             Defined in: fun3 ( d not visible)

Visible Variable:  a                Defined in: main ( b and c not visible)

Here variables c, d and e of fun2 are not visible

d. Main calls fun3; fun3 calls fun1

Here the main() calls fun3, fun3 calls fun1. This means the body of fun1 executes first, then of fun3 and then in last, of main()

Visible Variable: b, c, d     Defined in: fun1  

Visible Variable:   e, f        Defined in:  fun3   ( d not visible )

Visible Variable:    a          Defined in: main (b and c not visible)

e. Main calls fun1; fun1 calls fun3; fun3 calls fun2

Here the main() calls fun1, fun1 calls fun3 and fun3 calls fun2. This means the body of fun2 executes first, then of fun3, then of fun1 and then in last, of main()

Visible Variable: c, d, e        Defined in: fun2

Visible Variable:  f               Defined in: fun3 ( d and e not visible)

Visible Variable:  b               Defined in:  fun1 ( c and d not visible)

Visible Variable: a                Defined in: main ( b and c not visible)

f. Main calls fun3; fun3 calls fun2; fun2 calls fun1

Here the main() calls fun3, fun3 calls fun2 and fun2 calls fun1. This means the body of fun1 executes first, then of fun2, then of fun3 and then in last, of main()

Visible Variable: b, c, d       Defined in: fun1  

Visible Variable: e               Defined in: fun2  

Visible Variable: f                Defined in: fun3  

Visible Variable: a               Defined in: main

Answer:

Computer ethics is a part of practical philosophy concerned with how computing professionals should make decisions regarding professional and social conduct. Margaret Anne Pierce, a professor in the Department of Mathematics and Computers at Georgia Southern University has categorized the ethical decisions related to computer technology and usage into three primary influences:

The individual's own personal code.

Any informal code of ethical conduct that exists in the work place.

Exposure to formal codes of ethics.

Explanation:

Answer:

INSERT INTO categories (CategoryName)

VALUES ('Brass Code');

Explanation:

The SQL refers to the Structured Query Language in which the data is to be designed and maintained that occurred in the relational database management system i.e it is to be used for maintaining and query the database

Now the INSERT statement should be written as follows

INSERT INTO categories (CategoryName)

VALUES ('Brass Code');

Answer:

Here is the JAVA code:

public class Main{

public static int solution(int[] A) { //method that takes non-empty array A consisting of 0s and 1s

           int N = A.length; // number of 0s and 1s in array A

           int r = 0; //result of adjacency

           for (int i = 0; i < N - 1; i++;   )   { // iterates through A

               if (A[i] == A[i + 1])  //if i-th element of A is equal to (i+1)th element

                   r = r + 1;   }     //add 1 to the count of r

           if (r == N-1)   //for test cases like {1,1}

           {return r-1; }

           int max = 0; //to store maximum possible adjacency

           for (int i = 0; i <N; i++)   { //iterates through array

               int c = 0;

               if (i > 0)    { //starts from 1 and  covering the last

                   if (A[i-1] != A[i]) //checks if i-1 element of A is not equal to ith element of A

                       c = c + 1;    //adds 1 to counter variable

                   else

                      c = c - 1;   } //decrements c by 1

               if (i < N - 1)     {//starting with 0

                   if (A[i] != A[i + 1])  //checks if ith element of A is not equal to i+1th element of A

                       c = c + 1; //adds 1 to counter variable

                   else

                       c = c - 1;   }      //decrements c by 1        

               max = Math.max(max,c);   }  //finds the maximum of max and c

           return r + max;         } //returns result + maximum result

        public static void main(String[] args) {

   int[] A = {1, 1, 0, 1, 0, 0}; //sample array to test the method

   System.out.println(solution(A));} } //calls the method passing array to it

Explanation:

The program works as follows:

A[] = {1, 1, 0, 1, 0, 0}

N = A.length

N = 6

The A has the following elements:

A[0] =  1

A[1] = 1

A[2] = 0

A[3] = 1

A[4] = 0

A[5] = 0

Program iterates through array A using for loop. Loop variable i is initialized to 0

if condition if (A[i] == A[i + 1]) checks

if (A[0] == A[0 + 1])

A[0] =  1

A[0 + 1] = A[1] = 1

They both are 1 so they are equal

r = r + 1;  

Since the above if condition is true so 1 is added to the value of r Hence

r = 1

At each iteration of the loop the if condition checks whether the adjacent elements of A are equal. If true then r is incremented to 1 otherwise not.

So after all the iterations value of r = 2

if (r == N-1) evaluates to false because r=2 and N-1 = 5

So program moves to the statement:

for (int i = 0; i <N; i++)

This loop iterates through the array A

if (i > 0) condition checks if value of i is greater than 0. This evaluates to false and program control moves to statement:

if (i < N - 1) which makes if(0<5) This evaluates to true and program control moves to statement

if (A[i] != A[i + 1])  which means:

if (A[0] != A[0 + 1]) -> if (A[0] != A[1])

We know that

A[0] =  1

A[1] = 1

So this evaluates to false and else part is executed:

value of c is decremented to 1. So c=-1

max = Math.max(max,c) statement returns the max of max and c

max = 0

c = -1

So max = 0

value of i is incremented to 1 so i = 1

At next step:

if (i < N - 1) which makes if(1<5) This evaluates to true and program control moves to statement

if (A[i] != A[i + 1]) which means:

if (A[1] != A[1 + 1]) -> if (A[1] != A[2])

A[1] = 1

A[2] = 0

So the statement evaluates to true and following statement is executed

c = c + 1; The value of c is incremented to 1. So

c = -1 + 1

Hence

Hence c= 0, max = 0 and i = 2

next step:

if (i < N - 1) which makes if(2<5) This evaluates to true and program control moves to statement

if (A[i] != A[i + 1]) which means:

if (A[2] != A[2 + 1]) -> if (A[2] != A[3])

A[2] = 0

A[3] = 1

So the statement evaluates to true and following statement is executed

c = c + 1; The value of c is incremented to 1. So

c = 0 + 1

c = 1

Hence

The statement max = Math.max(max,c) returns the max of max and c

max = 0

c = 1

So max = 1

Hence  c= 1, max = 1 and i = 3

next step:

if (i < N - 1) which makes if(3<5) This evaluates to true and program control moves to statement

if (A[i] != A[i + 1]) which means:

if (A[3] != A[3 + 1]) -> if (A[3] != A[4])

A[3] = 1

A[4] = 0

So the statement evaluates to true and following statement is executed

c = c + 1; The value of c is incremented to 1. So

c = 1 + 1

c = 2

Hence

The statement max = Math.max(max,c) returns the max of max and c

max = 1

c = 2

So max = 2

Hence c= 2, max = 2 i = 4

next step:

if (i < N - 1) which makes if(4<5) This evaluates to true and program control moves to statement

if (A[i] != A[i + 1])  which means:

if (A[4] != A[4+ 1]) -> if (A[4] != A[5])

A[4] = 0

A[5] = 0

So this evaluates to false and else part is executed:

value of c is decremented to 1. So c=1

max = Math.max(max,c) statement returns the max of max and c

max = 2

c = 1

So max = 2

value of i is incremented to 1 so i = 5

next step:

if (i < N - 1) which makes if(5<5) This evaluates to false

if (i > 0) evaluates to true so following statement executes:

if (A[i-1] != A[i])

if (A[5-1] != A[5])

if (A[4] != A[5])

A[4] = 0

A[5] = 0

This statement evaluates to false so else part executes and value of c is decremented to 1

Hence

max = 2

c = 0

So max = 2

value of i is incremented to 1 so i = 6

The loop breaks because i <N evaluates to false.

Program control moves to the statement:

return r + max;

r = 2

max = 2

r + max = 2+2 = 4

So the output of the above program is:

4

Answer:

Answered below

Explanation:

Data hazards happen when instructions exhibiting data dependence modify data in the different stages of a pipeline. Potential data hazards when not attended to, can result in race hazards or race conditions. Examples of situations where data hazards can occur is read after write, write after read, write after write. To resolve data hazards we can insert a pipeline whenever a read after write, dependence is encountered, use out-of-order execution or use operand forwarding.

Structural hazards happen when multiple instructions which are already in pipeline new the same resource. Example is a situation which many instructions are ready to execute an there is a single Arithmetic Logic Unit. Methods for preventing this hazard include pipeline break an pipeline flushing.

Answer:

Such languages are used to create computer code or program code, the set of instructions forming a computer program which is executed by the computer. This source code is translated into machine code by a compiler or interpreter, so that the computer can execute it to perform its tasks.

Answer:

Writing code,” “coding,” and “programming” are basically interchangeable terms. Broadly speaking, knowing how to write code is the process of creating instructions that tell a computer what to do, and how to do it. Codes are written in various languages, such as javascript, C#, Python, and much more.

hlo samradhiki can we chat in comment section

Answer:

a. True

Explanation:

Cloud computing can be defined as a type of computing that requires shared computing resources such as cloud storage (data storage), servers, computer power, and software over the internet rather than local servers and hard drives.

Generally, cloud computing offers individuals and businesses a fast, effective and efficient way of providing services.

In Computer science, one of the most essential characteristics or advantages of cloud computing is rapid elasticity.

By rapid elasticity, it simply means that cloud computing gives you the ability to expand and reduce resources according to your specific service requirement because resources such as servers can be used to execute a particular task and after completion, these resources can then be released or reduced.

Some of the examples of cloud computing are Google Slides, Google Drive, Dropbox, OneDrive etc.

Answer:

Sequence of popped values: h,s,f.

State of stack (from top to bottom): m, d

Explanation:

Assuming that stack is  initially empty. Suppose that p contains the popped values. The state of the stack is where the top and bottom are pointing to in the stack. The top of the stack is that end of the stack where the new value is entered and existing values is removed. The sequence works as following:

push(d) -> enters d to the Stack

Stack:  

d ->top

push(h) -> enters h to the Stack

Stack:

h ->top

d ->bottom

pop() -> removes h from the Stack:

Stack:

d ->top

p: Suppose p contains popped values so first popped value entered to p is h

p = h

push(f) -> enters f to the Stack

Stack:

f ->top

d ->bottom

push(s) -> enters s to the Stack

Stack:

s ->top

f

d ->bottom

pop() -> removes s from the Stack:

Stack:

f ->top

d -> bottom

p = h, s

pop() -> removes f from the Stack:

Stack:

d ->top

p = h, s, f

push(m) -> enters m to the Stack:

Stack:

m ->top

d ->bottom

So looking at p the sequence of popped values is:

h, s, f

the final state of the stack:

m, d

end that is the top of the stack:

m

Answer:

Answered below

Explanation:

Hardware resources that can be usefully shared and also examples of their sharing include;

A) CPU servers, which carry out computations for clients.

B) Network capacity transmission of data or packet transmission is done using the same circuit, meaning many communication channels share the same circuit.

C) Screen networks windows systems which enable processes in remote computers to update the contents of their local server.

D) Memory cache server.

E) Disk file server, virtual disk server.

Softwares include;

A) Web-page web servers which allow client programs to have read-only access to page contents.

B) Database whose contents can be usefully shared.

C) File servers enable multiple users access to files .

D) Objects can be shared in distributed systems example shared ticket booking, whiteboard etc.

E) Exclusive lock which enables the coordination of accessing a special resource.

Why MUST you request your DSO signed I-20 ship as soon as it is ready and who is responsible to request the I-20?

a. It is required you have an endorsed/signed I-20 when Customs and Border Patrol or police ask for it

b. We only keep an unsigned digital copy and cannot sign an I-20 after the fact

c. It is against U.S. regulations to send digital (signed or not) DS-2019s and must treat I-20s the same

d. You will need all signed original I-20s to make copies to apply for OPT, STEM and H-1B in the future, so get them now!

e. It is the student’s choice to request each term, however, we cannot go back retroactively to provide past copies

f. We can only provide a signed copy of current I-20 and if changes occur from previous semesters that information will not show

g. The original endorsed I-20 signed by a DSO will be destroyed after 30 days of issuance if not picked up, and it cannot be replicated

h. The cost to have I-20 shipped may go up at any time

i. All the above

Answer:

i. All the above

Explanation:

DSO means designated school officials and they have to do with Student and Exchange Visitor Program (SEVP)-certified schools where students have to get a Form I-20, “Certificate of Eligibility for Nonimmigrant Student Status which provides information about the student's F or M status.

What a student must request for from his DSO signed I-20 ship are all the above options.

Answer:

Here is the Python program:

def fancy_find(search_within , search_for):  # function definition of fancy_find function that takes two parameters

   index = 0  #to store the index of search_within where the search_for string is found

   if search_for in search_within:  #checks if the string search_for is present in string search_within

       sf = search_for[0]  #points to the first character of the search_for

       for sw in search_within:  #iterates through search_within

           if sw == sf:  #if the first character of search_for is equal to the character at sw index of search_within

               if search_within[index:index+len(search_for)] == search_for:  #checks if the value of search_for is found in search_within

                   print(search_for,"found at index",index,"!")  #if above condition is true prints the message "[search_for] found at index [index]!", with [search_for] and [index] replaced by the value of search_for and the index at which it is found

                   return ""  

           index += 1  #increments value of index at each iteration

   print(search_for,"is not found within", search_within)  #if search_for is not found within search_within, prints message "[search_for] was not found within [search_within]!" with the values of search_for and search_within.

   return ""    

#following two statements are used to test the working of above function

print(fancy_find("ABCDEF", "DEF"))  #calls fancy_find() passing "ABCDEF" as search_within and "DEF" as search_for

print(fancy_find("ABCDEF", "GHI")) #calls fancy_find() passing "ABCDEF" as search_within and "GHI" as search_for

Explanation:

The program is well explained in the comments. I will explain the working of the function with the help of an example:

Suppose

search_within = "ABCDEF"

search_for = "DEF"

We have to find if search_for i.e. DEF is present in search_within i.e. ABCDEF

if search_for in search_within statement checks using in operator that if DEF is included in ABCDEF. Here this condition evaluates to true so the next statement sf = search_for[0]  executes which sets the first element of search_for i.e. D to sf. So sf = 'D'

for sw in search_within this statement has a for loop that iterates through ABCDEF and works as following:

At first iteration:

sw contains the first character of search_within  i.e. A

if sw == sf: condition checks if the first character of the search_for i.e. D is equal to sw i.e. A. Its not true so the program control moves to this statement:

index += 1 This increases the value of index by 1. index was initialized to 0 so now it becomes 1. Hence index=1

At second iteration:

sw contains the second character of search_within  i.e. B

if sw == sf: condition checks if the first character of the search_for i.e. D is equal to sw i.e. B Its not true so the program control moves to this statement:

index += 1 This increases the value of index by 1. index was initialized to 0 so now it becomes  2. Hence index=2

At third iteration:

sw contains the third character of search_within  i.e. C

if sw == sf: condition checks if the first character of the search_for i.e. D is equal to sw i.e. C Its not true so the program control moves to this statement:

index += 1 This increases the value of index by 1. index was initialized to 0 so now it becomes  3. Hence index=3

At fourth iteration:

sw contains the third character of search_within  i.e. D

if sw == sf: condition checks if the first character of the search_for i.e. D is equal to sw i.e. D. Its true so so the program control moves to this statement:

  if search_within[index:index+len(search_for)] == search_for:

current value of index=3

len(search_for) returns the length of DEF i.e. 3

So the if condition checks for the search_for in search_within. The statement becomes:

if search_within[3:3+3] == search_for:

search_within[3:3+3]  means from 3rd index position of search_within to 6-th index position of the search_within. This means from 4th element of search_within i.e. D to the last. Hence search_within[3:3+3] is equal to DEF.

search_for = DEF so

if search_within[3:3+3] == search_for: checks if

search_within[3:3+3] = DEF is equals to search_for = DEF

Yes it is true so

print(search_for,"found at index",index,"!") statement is executef which prints the following message:

DEF found at index 3!

This output is because search_for = "DEF" and index=3

Answer:

Here is the corrected code: The screenshot of the program along with its output is attached. The comments are written with each line of the program for better understanding of the code.

CarRental.java

public class CarRental  {  //class name

//below are the data members name, zipcode, size, dFee, days and total

String name;  

int zipcode;

String size;

double dFee;

int days;

double total;  

public String getName()  {  //accessor method to get the name

return name; }

public int getZipcode()  { //accessor method to get the zipcode

return zipcode; }

public String getSize() {  //accessor method to get the size

return size; }

public int getDays() {  //accessor method to get the days

return days;  }

public CarRental(String size)  {  //constructor of CarRental class

if(size.charAt(0)=='e')  // checks if the first element (at 0th index) of size data member is e

     dFee = 29.99;  // sets the dFee to 29.99

  else if(size.charAt(0)=='m')  // checks if the first element (at 0th index) of size data member is m

     dFee = 38.99;  // sets the dFee to 38.99

  else   // checks if the first element (at 0th index) of size data member is f

     dFee =43.50;  // sets the dFee to 43.50

   }

public void calculateTotal(int days) {  //method calculateTotal of CarRental

total = dFee*days;  }  //computes the rental fee

public void print()   {  //method to display the total rental fee

System.out.println("Your rental total cost is: $" + total);  } }

Explanation:

LuxuryCarRental.java

import java.util.*;

public class LuxuryCarRental extends CarRental {  //class LuxuryCarRental that is derived from class CarRental

public LuxuryCarRental(String size, int days) {  // constructor of LuxuryCarRental

super(size);}   //used when a LuxuryCarRental class and CarRental  class has same data members i.e. size

public void calculateTotal() {  //overridden method

super.calculateTotal(days); // used because CarRental  and LuxuryCarRental class have same named method i.e.  calculateTotal

dFee = 79.99;  //sets the rental fee at $79.99 per day

total = dFee;  }  //sets total to rental fee value

public void print(){  //overridden method

   int chauffeur;  // to decide to include chauffeur

Scanner keyboard = new Scanner(System.in);  //used to take input from user

System.out.println("Do you want to add a chauffeur for $200? Enter 0 for"

+ " yes and 1 for no");  // prompts the user to respond to the option of including a chauffeur at $200 more per day

chauffeur = keyboard.nextInt();   //reads the input option of chauffeur from user

if(chauffeur==1)  //if user enters 1 which means user does not want to add a chauffeur

total = dFee;  //then set the value of dFee i.e.  $79.99  to total

else  //if user enters 0 which means user wants to add a chauffeur

total = dFee + 200;  //adds 200 to dFee value and assign the resultant value to total variable

System.out.println("Your rental total cost is: $" + total);  }  } //display the total rental fee

UseCarRental.java

import java.util.*;

public class UseCarRental{ //class name

public static void main(String[] args){ //start of main() function body

String name, size; // declare variables

int zipcode, days; //declare variables

Scanner keyboard = new Scanner(System.in); // to take input from user

System.out.println("Enter total days you plan on renting: "); //prompts user to enter total days of rent

days = keyboard.nextInt(); // reads value of days from user

System.out.println("Enter your name: "); //prompts user to enter name

name = keyboard.next(); //reads input name from user

System.out.println("Enter your billing zipcode: "); // prompts user to enter zipcode

zipcode = keyboard.nextInt(); //reads input zipcode from user

System.out.println("Enter the size of the car: "); // prompts user to enter the value of size

size = keyboard.next(); //reads input size from user

CarRental economy = new CarRental(size); //creates an object i.e. economy of class CarRental

economy.calculateTotal(days); //calls calculateTotal method of CarRental using instance economy

economy.print(); //calls print() method of CarRental using instance economy

LuxuryCarRental fullsize = new LuxuryCarRental(size, days);  //creates an object i.e. fullsize of class LuxuryCarRental

fullsize.calculateTotal();  //calls calculateTotal method of LuxuryCarRental using instance fullsize

fullsize.print(); }} //calls print() method of LuxuryCarRental using instance fullsize      

Answer:

Kindly see explanation

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