If you know the answer please help me

Answer:

6.38548 years

Step-by-step explanation:

1 = 2 [tex]e^{42k}[/tex]

1/2 =   [tex]e^{42k}[/tex]

ln(1/2) = 42k ln(e)

ln(1/2)/42 = k

k = -0.01650

~~~~~~~~~~~~~~

45 = 50 [tex]e^{-0.01650t}[/tex]

45/50 =   [tex]e^{-0.01650t}[/tex]

ln(45/50) =  -0.01650 t ln(e)

ln(45/50)/ -0.01650 = t

t = 6.38548 years

The number of years for the radioactive element to reach a mass of 45 grams is given by t = 6.384129 years

The half-life of a radioactive isotope is the amount of time it takes for one-half of the radioactive isotope to decay. The half-life of a specific radioactive isotope is constant; it is unaffected by conditions and is independent of the initial amount of that isotope.

Half-life (symbol t½) is the time required for a quantity (of substance) to reduce to half of its initial value

The decay constant λ is = 0.693/t½

where t½ is the half-life of the element

Given data ,

Let the number of years be t

Let the initial mass of the element be a = 50 grams

The final mass of the element be ( a - x ) = 45 grams

Now , Element X is a radioactive isotope such that every 42 years, its mass decreases by half

And , half life t½ = 42 years

So , the decay constant k = 0.693/t½

k = 0.693 / ( 42 )

k = 0.0165

And , k= 2.303/t {log (a/a-x)}

So , t = 2.303 / ( 0.0165 ) log ( 50/45 )

On simplifying , we get

t = 6.384129 years

Hence , the number of years for the radioactive element to reach 45 grams is 6.384129 years

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The set of numbers are rational numbers but not integers whole numbers or natural numbers are { 1/2, 1/4, 1/8}.

Hence the third option is correct.

Use the concept of rational number defined as:

A rational number is a number that can be expressed as the quotient or fraction of two integers, where the denominator is not zero.

It can be represented as p/q,

Where p and q are integers and q is not equal to zero.

Examples of rational numbers include 1/2, -3/4, and 5/7.

Now analysing the given options we can see that,

The numbers 1/2, 1/4 and 1/8 are rational but not an integer.

Therefore,

The set  { 1/2, 1/4, 1/8} is the correct one, which is option third.

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Answer:

Leo's weight at the end of the fourth week = 181.7 pounds

Step-by-step explanation:

Leo's initial weight = 190 pounds

First week = lost 4.3 pounds

New weight = 190 pounds - 4.3 pounds

= 185.7 pounds

Second week = lost 2.8 pounds

New weight = 185.7 pounds - 2.8 pounds

= 182.9 Pounds

Third week = gained 0.7 pounds

New weight = 182.9 pounds + 0.7 pounds

= 183.6 pounds

Fourth week = lost 1.9 pounds

New weight = 183.6 pounds - 1.9 pounds

= 181.7 pounds

Leo's weight at the end of the fourth week = 181.7 pounds

Alternatively

New weight = initial weight - first week - second week + third week - fourth week

= 190 - 4.3 - 2.8 + 0.7 - 1.9

= 181.7 pounds

Answer:

a) its root 2

b) 2

c) 3,4,5,6 (just all x numbers)

d) inverse is just reverse of points ex: (2,1) for the first set

also what is that equation up top am i suppose to use that for something

Step-by-step explanation:

Answer:

90

Step-by-step explanation:

If they put 50 sheets per box, then it is just simple division.

4,500 divided by 50 is 90.

Answer:

90 boxes

Step-by-step explanation:

They need to ship 4500 sheets of paper.

They put 50 pages in each box.

# of boxes they will need = amount of paper / amount of paper they put in each box

# of boxes they will need = 4500 / 50 = 90

Answer:

A number that describes both the direction and the steepness of the line is known as slope of the line .

Answer:

mostly rational but sometimes irrational

Answer:

Not valid

Step-by-step explanation:

Because 12 is minor than 15

The conjecture is not valid.

Mandy not gets a bonus.

Given that:

If a computer sales person sells at least 15 computers in a week, then she gets a bonus.

Maddy sells 12 computers in a week.

Conclusion: Maddy gets a bonus.

We have to check the conjecture is valid or not.

What is Conjecture?

A conjecture is a conclusion or proposition that is proffered on the tentative basis without the proof.

Now,

Here, if a person sells 15 or more computers in a week, she gets a bonus.

Maddy sells 12 computers in a week, which is less than 15.

So, Maddy did not get a bonus.

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[tex]\boxed{\sf Discount=CP-SP}[/tex]

[tex]\\ \sf\longmapsto Discount=700-524[/tex]

[tex]\\ \sf\longmapsto Discount=176[/tex]

Answer:

cost price(cp)=rs.700

sold price(sp)=rs.524

discount =cp-sp

discount =700-524

discount =rs.176

Answer:

P(x) = 4n+5

P(4) = 4(4)+5

P(4) = 16+5

P(4) = 21

The answer is 21.

Let me know if this helps!

I thing W,Y is righ am i right.

Answer:

186,250 rs

Step-by-step explanation:

So

149m is the whole space

0.2m is one tile space

250 rs = 0.2 tiles (so 250=1)

so if there is

Answer:

ratio of Sophia's sweets to Isabel's sweets is

13:8

Answer:

you first have to find the number of sweets that sophia got.by subtracting the total number of sweets minus the number of sweets that isabel got which will be

42-16=26

therefore the ratio will be

16:26

8:13

I hope this helps

[tex]\huge\text{Hey there!}[/tex]

[tex]\large\textsf{There is approximately 5 branches of chemistry.}\\\\\large\textsf{The branches are...}}\\\\\bullet\large\text{Analytical chemistry}\\\bullet\large\text{Biochemistry}\\\bullet\large\text{Inorganic chemistry}\\\bullet\large\text{Physical chemistry}\\\bullet\large\text{Organic chemistry}[/tex]

[tex]\star\large\textsf{\ \underline{\underline{Analytical chemistry}} is the science that prevails, communicates, and}\\\large\textsf{process the information about its arrangement of the matter.}\\\\\star\large\textsf{\ \underline{\underline{Biochemistry}} is the study of the process in the cellular \& molecular}\\\large\textsf{level}[/tex]

[tex]\star\large\textsf{\ \underline{\underline{Inorganic chemistry}} is the behavioral mood of the inorganic and the} \\\large\textsf{organometallic compounds. It is distributed with the synthesis.}\\\\\star\large\textsf{\ \underline{\underline{Physical chemistry}} is the changing and exchange of the materials.}[/tex]

[tex]\star\large\textsf{\ \underline{\underline{Organic chemistry}} is the study of the structure, property,}\\\large\textsf{(or properties) \& reactions of the organic compounds}[/tex]

[tex]\large\boxed{\frak{Good \ luck \ on \ your \ assignment \ \& \ enjoy\ your\ day!}}[/tex]

~[tex]\rm{Amphitrite1040:)}[/tex]

Answer:

A. 28°

Step-by-step explanation:

Since sides AC and AB are congruent, their opposite angles are congruent.

m<B = m<C = 28°

Answer: A. 28°

Answer:

The answer is A

Step-by-step explanation:

What you have is an isosceles triangle. AC = AB <A cannot be 28 degrees so the triangle is not equilateral.

If the 2 sides are equal, the 2 angles opposite these equal sides are also equal.

<B = <C

<C = 28 degrees

<B = 28 degrees

2/3 divided by -2

now,

answer= 2/3×1/2

we need to receprocal the number if we have to change division into multiplication...

= 1/3

we cut 2 as it is equal and present in both denomenator and numerator....

Answer:

-2/6

Step-by-step explanation:

Answer:

It is 9.5

Step-by-step explanation:

[tex] = (89.3 \times 0.51 )\div 4.8[/tex]

first solve the bracket:

[tex] = (45.543) \div 4.8 \\ = 9.488[/tex]

Answer:

20, 30

Step-by-step explanation:

let the intergers be x and y

x = 2/3y

from this eqn, we know that y is larger.

hence, y-x=10

y-2/3y=10

1/3y=10

y=30

x=2/3y =2/3(30) = 20

Answer:

37.68

Step-by-step explanation:

The formula for circumference is 2*pi*r plug in 6 for the radius to get 2*3.14*6 simplify to get 37.68

[tex]\rm \: \hookrightarrow \:\:Circumference \: \: of \: \: circle \: = \: 2 \: \pi \: r[/tex]

[tex]\bf \large \: \implies \:\:2 \: \times \: 3.14 \: \times \: 6[/tex]

[tex]\bf \large \: \implies \:\:6.28 \: \times \: 6[/tex]

[tex]\bf \large \: \implies \:\:37.68 \: \: inches[/tex]

Answer:

4 sqrt(3)

Step-by-step explanation:

sqrt(3) * sqrt(16)

sqrt(3) *4

4 sqrt(3)

Answer: d

Step-by-step explanation: I took the test

Answer:

120

Step-by-step explanation:

Given,

t = 2

s = 10

3 t^2 s

= 3 x 2^2 x 10

= 3 x 4 x 10

= 120

Answer:

Step-by-step explanation:

Hello!

t² = 2²=4

3*4*10 = 120

Answer:

20% Increase

Step-by-step explanation:

Percentages can be put vice versa. So 20% Of 50 = 50% Of 20 Which Equals 10.

Mark me as brainliest please

Answer:

All registered voters in Cleveland and the maximum percentage increase in taxes

Answer:

3x(4x+5y)

Step-by-step explanation:

to factorise this equation you have to remove the common terms,or the common factors in this case the common factor for both sides is 3 and the common letter is x

12x²+15xy

3x(4x+5y)

I hope this helps

Hi, I'm happy to help!

for a box an whisker plot, maximum and minimum values on the edge of the lines. The maximum shown here is 8, because the line ends there. The minimum is -8 because the line ends there.

The median value is shown by the middle line, which is 4.

To sum it up: Maximum: 8, Minimum: -8, Median: 4\

I hope this was helpful, keep learning! :D

DCB form a right angle which is 90 degrees.

The two inside angles need to equal 90

ACB = 90-65 = 25

Answer: 25

Answer:

25

Step-by-step explanation:

its correct

Answer:

The domain is the whole R-{0} and the range is R

Answer:

0

Step-by-step explanation:

0

Number planes contain points J, K and N is 0. Therefore, option A is the correct answer.

A plane in geometry is a level surface that never ends. Other names for it include a two-dimensional surface. A plane has an unlimited width, an endless length, zero thickness, and no curvature.

Given that, X and Y are planes.

In the given figure, point J lies outside the X and Y planes.

Points K and N are lies on plane X.

So, J, K and N are not lying in the same plane.

Therefore, option A is the correct answer.

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Answer:

30.

Step-by-step explanation:

x^2 = 24^2 + 18^2

x^2 = 576 + 324 = 900

x = sqrt900 = 30.