Step-by-step explanation:
The roots are equal, so the discriminant equals 0.
b² − 4ac = 0
(2k)² − 4 (k²−1) (3k+1) = 0
4k² − 4 (3k³ + k² − 3k − 1) = 0
k² − (3k³ + k² − 3k − 1) = 0
k² = 3k³ + k² − 3k − 1
0 = 3k³ − 3k − 1
Suppose the probability of an athlete taking a certain illegal steroid is 10%. A test has been developed to detect this type of steroid and will yield either a positive or negative result. Given that the athlete has taken this steroid, the probability of a positive test result is 0.995. Given that the athlete has not taken this steroid, the probability of a negative test result is 0.992. Given that a positive test result has been observed for an athlete, what is the probability that they have taken this steroid
Answer:
93.25% probability that they have taken this steroid
Step-by-step explanation:
Bayes Theorem:
Two events, A and B.
[tex]P(B|A) = \frac{P(B)*P(A|B)}{P(A)}[/tex]
In which P(B|A) is the probability of B happening when A has happened and P(A|B) is the probability of A happening when B has happened.
In this question:
Event A: Positive test
Event B: Taking the steroid.
Suppose the probability of an athlete taking a certain illegal steroid is 10%.
This means that [tex]P(B) = 0.1[/tex]
Given that the athlete has taken this steroid, the probability of a positive test result is 0.995.
This means that [tex]P(A|B) = 0.995[/tex]
Positive test:
99.5% of 10%(If the athlete has taken).
100-99.2 = 0.8% of 100-10 = 90%(Athlete has not taken)
Then
[tex]P(B) = 0.995*0.1 + 0.008*0.9 = 0.1067[/tex]
Given that a positive test result has been observed for an athlete, what is the probability that they have taken this steroid
[tex]P(B|A) = \frac{P(B)*P(A|B)}{P(A)} = \frac{0.1*0.995}{0.1067} = 0.9325[/tex]
93.25% probability that they have taken this steroid
100 POINTS
PLEASE PROVIDE STEPS. FOR BOTH
FIND THE INTEGRALS
Answer:
8. -⅓ cos³x + C
9. sec x + eˣ + C
Step-by-step explanation:
8. ∫ sin x cos²x dx
If u = cos x, then du = -sin x dx.
∫ -u² du
-⅓ u³ + C
-⅓ cos³x + C
9. ∫ (sec x tan x + eˣ) dx
∫ sec x tan x dx + ∫ eˣ dx
These are both standard integrals:
sec x + eˣ + C
Question 8:
∫sinxcos²xdx
∫-u²du (let u = cos(x))
-∫u²du
-u(^2+1)/2+1
-cos^(2+1)(x)/2+1
-1/3cos³(x)
-1/3cos³(x) + C
Question 9:
∫(secxtanx + eˣ)dx
∫sec(x)tan(x)dx + ∫eˣdx (apply sum rule)
sec(x) + eˣ (sec(x)tan(x)dx = sec(x) and eˣdx = eˣ)
sec(x) + eˣ + C
Best of Luck!
John wants to invest P dollars at a 4% interest rate. After 5 years the investment will be worth 2000 dollars. How much will it be worth in 11 years?
Answer:
About $2530.63
Step-by-step explanation:
The formula for this kind of calculation is [tex]A=P(1+\frac{r}{n})^{nt}[/tex], where P is the initial investment, r is the interest rate, n is the number of times you compound your investment per year, and t is the number of years. Assuming that you compound yearly, plugging in the numbers that you have given, you are left with:
[tex]2000=P(1+\frac{0.04}{1})^{t}[/tex]
[tex]2000=P\cdot (1.04)^5\\P\approx 1643.85\\A=1643.85 \cdot (1.04)^{11}\approx $2530.63[/tex]
Hope this helps!
What is the area of a rectangle with sides length of 5/12 feet and 2/3 feet
Answer:
The answer is 10/36 or if you want to simplify, 5/18
Step-by-step explanation:
To solve the area of a rectangle, you need to multiply the sides with each other, so 5/12 x 2/3 is 10/36 (unsimplified) . You multiply the numerators and then the denominators and simplify.
There are 14math teachers and 26 science teachers at school today. What is the ratio of math teachers to math and science teachers at school?
It's basically asking "what is the ratio of math teachers to total teachers?" assuming there are only math and science teachers at this school. For the sake of simplicity, let's just go with that. We have 14 math teachers and 14+26 = 40 teachers total. The ratio of math to total is 14:40 which reduces to 7:20 when we divide both parts of the ratio by the GCF 2.
Answer: 7: 13
The ratio would be 14: 26, however you are most likely asked to simplify it. Which is why the answer would be 7: 13
I hope this helped! :DD
Trisomy 18 (T18) is a rare genetic disorder that severely disrupts a baby's development prior to birth. Many die before birth and most die before their first birthday. T18 occurs in only 1 in 2500 pregnancies in the U.S. A genetic test on the mother's blood can be done to test for T18 in her baby. The overall probability of a positive test result is 0.010384. The probability of a positive test result for a baby with T18 is 0.97. The probability of a negative test result for a baby without T18 is 0.99. A mother's blood tests positive for T18. What is the probability that her baby has T18
Answer:
3.74% probability that her baby has T18
Step-by-step explanation:
Bayes Theorem:
Two events, A and B.
[tex]P(B|A) = \frac{P(B)*P(A|B)}{P(A)}[/tex]
In which P(B|A) is the probability of B happening when A has happened and P(A|B) is the probability of A happening when B has happened.
In this question:
Event A: Positive test.
Event B: The baby having T18.
T18 occurs in only 1 in 2500 pregnancies in the U.S.
This means that [tex]P(B) = \frac{1}{2500} = 0.0004[/tex]
The probability of a positive test result for a baby with T18 is 0.97.
This means that [tex]P(A|B) = 0.97[/tex]
The overall probability of a positive test result is 0.010384.
This means that [tex]P(A) = 0.010384[/tex]
What is the probability that her baby has T18
[tex]P(B|A) = \frac{0.0004*0.97}{0.010384} = 0.0374[/tex]
3.74% probability that her baby has T18
Barnes and Nobles buys a book for $14.25. They markup the price of the book by 35%.
Answer:
$19.24
Step-by-step explanation:
Take 14.25 times 1.35.
The markup rate will be 35% when the cost of the book is $14.25 and sells for $19.237.
What is the markup rate?The markup rate is computed by dividing a unit's gross profit (its sales price less its cost to create or buy for resale) by its cost.
Barnes and Noble buy a book for $14.25. They mark up the price of the book by 35%.
As per the question, we have
cost = $14.25
markup rate = 35% = 0.35
Let's x represent markup for the book,
markup rate = markup/sale price × 100%
35% = x / $14.25
0.35 = x / $14.25
x = $14.25 × 0.35
Apply the multiplication operation, and we get
x = 4.9875
So sale price = markup + cost
So sale price = $4.9875 + $14.25
So sale price = $19.237
Thus, the markup rate will be 35% when the cost of the book is $14.25 and sells for $19.237.
To learn about the markup rate click here:
brainly.com/question/11999225
#SPJ2
Writing Percents as Fractions
a. Write 35% as a fraction in simplest form.
35% =
35
100
Write as a fraction with
a denominator of 100.
7
20
Simplity.
Answer:
Answers are below
Step-by-step explanation:
Percent means "out of 100" so 35% is 35/100. We can simplify this fraction by dividing the numerator and denominator by 5. 35/100 / 5 = 7/20.
7/20 multiply the numerator and denominator by 5.
7/20 x 5 = 35/100
If this answer is correct, please make me Brainliest!
Answer:
b and c
Step-by-step explanation:
what is the value of the rational expression below when x is equal to 4? x+20/x+4
Answer:
3
Step-by-step explanation:
All we need to do here is plug in the number 4 for the variable x. Wherever there's an x, kidnap it and replace it with a 4!
[tex]\frac{x + 20}{x + 4}[/tex]
x = 4
[tex]\frac{4 + 20}{4 + 4}[/tex]
Do the addition.
4 + 20 = 24
4 + 4 = 8
[tex]\frac{24}{8}[/tex]
We can simplify this! What is 24 divided by 8?
24/8 = 3
The answer is 3!
A friendly contest involves randomly drawing a marble from a bag that contains 16 blue marbles, 12 red
marbles, and 8 yellow marbles. If a blue marble is drawn, Nathan wins. If a red marble is drawn, Taylor wins.
If a yellow marble is drawn, Cady wins.
Who is most likely to win the contest?
1 Nathan
2 Cady
3 They are equally likely to win.
4 Taylor
Answer: I have a huge feeling it would be Nathan because he has the most blue marble. Yk?
The Sears Tower, at 1,451 feet, is one of the tallest structures in the United States. A penny is thrown from the top of the tower. The height, h, of the penny is recorded after each second, t, in the table. Write an equation for the curve of best fit, then find the approximate height of the penny after 7 seconds.
Answer:
The equation for the height of the penny in function of time is:
[tex]h(t)=1451-16t^2[/tex]
After 7 seconds, the penny will be at a height of 667 feet.
Step-by-step explanation:
The penny will have a free fall.
The initial velocity is zero, and the initial height is h(0)=1,451.
The acceleration will be the gravity, that has a value g=32 ft/s^2.
Then, we can model this starting by the speed:
[tex]dv/dt=-g\\\\v(t)=v_0-gt=-gt[/tex]
Then, the height becomes:
[tex]dh/dt=v(t)=-gt\\\\h(t)=h_0-\dfrac{gt^2}{2}=1451-\dfrac{32}{2}t^2\\\\\\h(t)=1451-16t^2[/tex]
The approximate height of the penny after 7 seconds can be calculated as:
[tex]h(7)=1451-16(7^2)=1451-16*49=1451-784=667[/tex]
After 7 seconds, the penny will be at a height of 667 feet.
What’s the answer to this question ?
Answer:
the correct choice is marked
Step-by-step explanation:
The zero-crossings at -3 and +3 tell you that one of the factors is the difference of squares:
(x +3)(x -3) = x^2 -9
The zero crossing at -1 tells you that x+1 is a factor.
So, the polynomial factors as ...
f(x) = (x^2 -9)(x +1)
Multiplying this out, we get ...
f(x) = x^2(x +1) -9(x +1)
f(x) = x^3 +x^2 -9x -9 . . . . . . matches the first choice
Estimate the sum of 17.36 and 8.7 BY ROUNDNG TO THR NEAREST WHOLE NUMBER BEFORE ADDING...?
A.9
B.10
C.25
D.26
E. None correct
Answer:
D. 26
Step-by-step explanation:
We have to round to whole numbers before adding.
When approximating to whole numbers, if the number after the decimal is less than 5, you round down to 0 but if it is greater or equal to 5, you round up to 1.
17.36 ≅ 17
8.7 ≅ 9
Therefore:
17 + 9 = 26
Determine the y-intercept of the function.
x = 4y - 6
Answer:
y = 3/2
Step-by-step explanation:
Answer:
x=4y-6
Geometric figure: Straight Line
Slope = 0.500/2.000 = 0.250
x-intercept = -6/1 = -6.00000
y-intercept = 6/4 = 3/2 = 1.50000
Rearrange:
Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation :
x-(4*y-6)=0
Step by step solution :
Step 1 :
Equation of a Straight Line
1.1 Solve x-4y+6 = 0
Tiger recognizes that we have here an equation of a straight line. Such an equation is usually written y=mx+b ("y=mx+c" in the UK).
"y=mx+b" is the formula of a straight line drawn on Cartesian coordinate system in which "y" is the vertical axis and "x" the horizontal axis.
In this formula :
y tells us how far up the line goes
x tells us how far along
m is the Slope or Gradient i.e. how steep the line is
b is the Y-intercept i.e. where the line crosses the Y axis
The X and Y intercepts and the Slope are called the line properties. We shall now graph the line x-4y+6 = 0 and calculate its properties
Graph of a Straight Line :
Calculate the Y-Intercept :
Notice that when x = 0 the value of y is 3/2 so this line "cuts" the y axis at y= 1.50000
y-intercept = 6/4 = 3/2 = 1.50000
Calculate the X-Intercept :
When y = 0 the value of x is -6/1 Our line therefore "cuts" the x axis at x=-6.00000
x-intercept = -6/1 = -6.00000
Calculate the Slope :
Slope is defined as the change in y divided by the change in x. We note that for x=0, the value of y is 1.500 and for x=2.000, the value of y is 2.000. So, for a change of 2.000 in x (The change in x is sometimes referred to as "RUN") we get a change of 2.000 - 1.500 = 0.500 in y. (The change in y is sometimes referred to as "RISE" and the Slope is m = RISE / RUN)
Slope = 0.500/2.000 = 0.250
Geometric figure: Straight Line
Slope = 0.500/2.000 = 0.250
x-intercept = -6/1 = -6.00000
y-intercept = 6/4 = 3/2 = 1.50000
Step-by-step explanation:
What is the volume of a cylinder with a base radius of 4 and height 7?
Answer:
351.86
Step-by-step explanation:
j+ 12 =25 find the solution to equation algebtaically
Answer:
j= 13
just subtract 12 from 25
Start by isolating the j.
Subtract 12 from both sides.
On the left, the 12 and -12 cancel.
On the right, 25 - 12 is 13.
So we have j = 13.
25 POINTS IF YOU GET THIS ONE RIGHT! VERY HARD
Answer:1.A 2.C 3.A 4.B
Step-by-step explanation:
1. (answer) a- 257 grams.
2. (answer) c. 1.18 kilometers.
3. (answer) b. 56.
4. (answer) a. 14 7/8 pounds.
what is this phrase in numerical expression
triple the sum of seventeen and ten
pls help
Answer: so you would do 17 plus ten which is 27 so triple 3 so your answer is 27^3
Step-by-step explanation:
sum so your adding plus you need the exponent which is times 3
€1.4 m
1.9 m
Tim has to cover 3 tanks completely with paint.
Each tank is in the shape of a cylinder with a top and a bottom.
The tank has a diameter of 1.4 metres and a height of 1.9 m.
A tin of paint covers 5 m
Find the total surface area of the 3 tanks and state how
many tins of paint Tim will need to buy
You must show your working
Total marks 5
Answer:
Step-by-step explanation:
Since each tank is cylindrical, we would apply the formula for determining the total surface area of a cylinder which is expressed as
Total surface area = 2πr² + 2πrh
Where
r represents the height of the cylinder.
h represents the height of the cylinder.
π = 3.14
From the information given,
Height = 1.9
Diameter = 1.4
Radius = diameter/2 = 1.4/2 = 0.7
Total surface area = 2 × 3.14 × 0.7² + 2 × 3.14 × 0.7 × 1.9 = 3.0772 + 8.3524 = 11.4296 m²
Total surface area of the 3 cylinders = 11.4296 × 3 = 34.29 m²
Since a tin of paint covers 5 m², the number of tins paints that Tim will need to buy is
34.29/5 = 6.858
Since the tins of paint must be whole numbers, he needs to buy 7 tins of paints.
Shira packs 170 lemon bars in boxes for the bake sale. Each box holds 8 lemon bars. She takes home the lemon bars tha are leg over after she has filled as many boxes as possible. Ahora use partial quotients to find how many boxes of lemon bars she can fill to sell at the bake sale. She finds only two partial quotients when she divides. Use the numbers in the box to answer the questions
1 2 7 8 20 21 23 27 29
Question:
1. How many full boxes of lemon bars can Shira fill?
2. How many delicious lemon bars will she be taking home?
Answer:
1. Number of filled box = 21
2. Number of take home = 2
Step-by-step explanation:
Given
Number of lemon bars = 170
Each bar contains 8 lemon bars
Required
(1) & (2)
To calculate the number of boxes Shira can fill, we simply divide the total number of bars by constituents of each bar .
i.e.
Number of filled box = 170/8
Number of filled box = 21.25
But here, we only need the quotient of the division because it represents the filled boxed.
So,
Number of filled box = 21
Calculating the number of take home.
We'll follow the same steps as (1) above but here, we only need the remainder of the division.
When 170 is divided by 8, the remainder is 2.
So, number of boxes she'll take home is 2.
See calculation below
Number of take home = 170 % 8
Number of take home = 2
The answer to the volume of a sphere/hemisphere should only be written as a(n)
Answer:
Cubic unit.Step-by-step explanation:
The answer to the volume of a sphere/hemisphere should only be written a cubic unit, because volumes depends on three coordinates to be defined, width, lenght and height, where each coordinates is a length itselft, which multiplied give a cubic length unit, due to the power properties.
For example, imagine that you have all three dimensions in meters, then the product would be [tex]m \times m \times m=m^{3}[/tex].
Therefore, the answer that completes the statment is cubic unit. A volume should be always written in cubic units.
Answer:
The answer to the volume of a sphere/hemisphere should only be written as a function of the radius.
Step-by-step explanation:
An hemisphere is half of a sphere. Its volume can be determined by dividing the volume of a given sphere by 2. The volume is the maximum space or capacity that a 3 dimensional object occupies.
volume of a sphere = [tex]\frac{4}{3}[/tex] [tex]\pi[/tex] [tex]r^{3}[/tex]
volume of an hemisphere = [tex]\frac{2}{3}[/tex] [tex]\pi[/tex] [tex]r^{3}[/tex]
In both cases, the volume is dependent on the value of radius.
The answer to the volume of a sphere/hemisphere should only be written as a function of the radius. Volume is measured in cubic units.
Three methods, A, B and C, are available for teaching a certain industrial skill. The failure rate is 15% for A, 5% for B and 10% for C. The method A is used 30%, B is used 40% and C is used 30% of the time. A worker is taught the skill by one of the methods but fails to learn it correctly. a. (10 points) What is the probability that he was taught by method A? b. (5 points) What is the probability of B given A?
Answer:
a) so the correct answer is that the probability that method A has been taught is 0.4737
b) the probability that B receives A is 0.5
Step-by-step explanation:
With the previous data we know that 3 methods teach an industrial skill and when putting into practice a worker does not learn, we have the failure rates like this:
method A fails 15%
method B fails: 5%
method C fails: 10%
usage percentages:
A: 30%
B: 40%
C: 30%
a) the probability that method A has been taught is as follows:
P (failure rate) = P (A) * P (failure rate A) + P (B) * P (failure rate B) + P (C) * P (failure rate C)
we replace the data obtaining:
P = 0.3 * 0.15 + 0.4 * 0.05 + 0.3 * 0.1 = 0.095
P ( failure rate A) = P (A) * P (failure rate A) / P (failure rate)
we replace the data obtaining:
0.3 * 0.15 / 0.095 = 0.4737
so the correct answer is that the probability that method A has been taught is 0.4737
b) the probability that B receives A is as follows:
P (B | A) = P (B) = 0.50
The quality control manager at a light bulb factory needs to estimate the mean life of a batch (population) of light bulbs. We assume that the population standard deviation is 100 hours. A random sample of 64 light bulbs from the batch yields a sample mean of 350. a) Construct a 95% confidence interval for the population mean of light bulbs in this batch. b) Do you think that the manufacturer has the right to state that the average life of the light bulbs is 400 hours
Answer:
a)95% confidence intervals for the population mean of light bulbs in this batch
(325.5 ,374.5)
b)
The calculated value Z = 4 > 1.96 at 0.05 level of significance
Null hypothesis is rejected
The manufacturer has not right to take the average life of the light bulbs is 400 hours.
Step-by-step explanation:
Given sample size n = 64
Given mean of the sample x⁻ = 350
Standard deviation of the Population σ = 100 hours
The tabulated value Z₀.₉₅ = 1.96
95% confidence intervals for the population mean of light bulbs in this batch
[tex](x^{-} - Z_{\frac{\alpha }{2} } \frac{S.D}{\sqrt{n} } , x^{-} + Z_{\frac{\alpha }{2} }\frac{S.D}{\sqrt{n} } )[/tex]
[tex](350 - 1.96\frac{100}{\sqrt{64} } , 350 + 1.96\frac{100}{\sqrt{64} } )[/tex]
[tex](350 -24.5, 350 +24.5)[/tex]
(325.5 ,374.5)
b)
Explanation:-
Given mean of the Population μ = 400
Given sample size n = 64
Given mean of the sample x⁻ = 350
Standard deviation of the Population σ = 100 hours
Null hypothesis : H₀:The manufacturer has right to take the average life of the light bulbs is 400 hours.
μ = 400
Alternative Hypothesis: H₁: μ ≠400
The test statistic
[tex]Z = \frac{x^{-}-mean }{\frac{S.D}{\sqrt{n} } }[/tex]
[tex]Z = \frac{350 -400}{\frac{100}{\sqrt{64} } }[/tex]
|Z| = |-4|
The tabulated value Z₀.₉₅ = 1.96
The calculated value Z = 4 > 1.96 at 0.05 level of significance
Null hypothesis is rejected.
Conclusion:-
The manufacturer has not right to take the average life of the light bulbs is 400 hours.
Priscilla’s grandmother’s fruit salad recipe calls for one part apple, one part orange, four parts strawberry, two parts cherry, and three parts grape. Priscilla uses the same measuring cup to measure all of the fruit, so one part is equal to one cup of diced fruit. In this exercise, you will compare the quantities in the recipe to understand ratios better.
Answer:
There are 11 parts of fruit: 4-strawberry, 3- grape, 2, cherry, 1- apple, 1-orange 4/11 from the entine quantity of fruits- strawberry
3/11-grapes
2/11- cherries
1/11- apples
1/11- oranges } ⇒ the quantity of oranges and apples are equal Hope it helps ;>
If u(x)=-2x^2+3 and v(x)=1/x, what is the range of (uov)(x)
Answer:
Do my question i will do yours
Step-by-step explanation:
Answer:
The Answer is C
Step-by-step explanation:
In the past, 19% of all homes with a stay-at-home parent had the father as the stay-at-home parent. An independent research firm has been charged with conducting a sample survey to obtain more current information. (a) What sample size is needed if the research firm's goal is to estimate the current proportion of homes with a stay-at-home parent in which the father is the stay-at-home parent with a margin of error of 0.03? Use a 95% confidence level. (Round your answer up to the nearest whole number.)
Answer:
A sample size of 657 is needed.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which
z is the zscore that has a pvalue of [tex]1 - \frac{\alpha}{2}[/tex].
The margin of error is:
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
95% confidence level
So [tex]\alpha = 0.05[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.05}{2} = 0.975[/tex], so [tex]Z = 1.96[/tex].
In the past, 19% of all homes with a stay-at-home parent had the father as the stay-at-home parent.
This means that [tex]\pi = 0.19[/tex]
(a) What sample size is needed if the research firm's goal is to estimate the current proportion of homes with a stay-at-home parent in which the father is the stay-at-home parent with a margin of error of 0.03?
A sample size of n is needed.
n is found when [tex]M = 0.03[/tex]
Then
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
[tex]0.03 = 1.96\sqrt{\frac{0.19*0.81}{n}}[/tex]
[tex]0.03\sqrt{n} = 1.96\sqrt{0.19*0.81}[/tex]
[tex]\sqrt{n} = \frac{1.96\sqrt{0.19*0.81}}{0.03}[/tex]
[tex](\sqrt{n})^{2} = (\frac{1.96\sqrt{0.19*0.81}}{0.03})^{2}[/tex]
[tex]n = 656.91[/tex]
Rounding up to the nearest whole number.
A sample size of 657 is needed.
Consider the graph of the exponential function, y =3(2)^x. The x- intercept of the graph is
Answer:
the x intercept is 2
Step-by-step explanation:
I just went over this unit
Answer:
2
Step-by-step explanation:
What is the quotient?
(6 * 108) = (1.5 x 10-4)
4 x 1012
4 x 104
4 x 10-32
4 * 10-2
Answer:
The first choice.
Step-by-step explanation:
6 * 10^8 / 1.5 * 10^-4
= (6/1.5) * (10^(8 - (-4))
= 4 * 10^12.
Answer:
4 x 1012
Step-by-step explanation:
How do I type in exponents
Answer:
on what
Step-by-step explanation: normaly you have a button that you can have certain characters
Jay earns $8 an hour when he works at his uncle’s store. He earns $9 an hour when he does yard work for his neighbor. Which expression represents the total amount he will earn in a week when he works u hours at his uncle’s store and v hours doing yard work for his neighbor?
Answer:
8u+9v
Step-by-step explanation:
Answer:
8u+9v
Step-by-step explanation:
