Element X is a radioactive isotope such that every 30 years, its mass decreases by half. Given that the initial mass of a sample of Element X is 100 grams, how long would it be until the mass of the sample reached 64 grams, to the nearest tenth of a year?

Answers

Answer 1

Answer:

19.3 years

Step-by-step explanation:

Given that the initial mass of a sample of Element X is 100 grams,

The formula is given as:

N(t) = No × (1/2) ^t/t½

Element X is a radioactive isotope such that every 30 years, its mass decreases by half.

N(t) = Mass after time (t)

No = Initial mass = 100 grams

t½ = Half life = 30 grams

N(t) = 100 × (1/2) ^t/30

How long would it be until the mass of the sample reached 64 grams, to the nearest tenth of a year?

This means we are to find the time

N(t) = 100 × (1/2) ^t/30

N(t) = 64 grams

64 = 100(1/2)^t/30

Divide both sides by 100

64/100 = 100(1/2)^t/30/100

0.64 = (1/2)^t/30

Take the Log of both sides

log 0.64 = log (1/2)^t/30

log 0.64 = t/30(1/2)

t = 19.315685693242 years

Approximately = 19.3 years


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Answer:

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Step-by-step explanation:

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Answer:

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Answer:

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Step-by-step explanation for #3:

[tex]tan(\frac{x}{12}) =24[/tex]          Use tangent function because it relates to the opposite and adjacent sides of the triangle.

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If you have any more questions, feel free to ask and I'll answer them in the comments section under this answer. Please consider marking my answer as Brainliest, because it really helps me out.

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cuanto es 1+1
respuestas originales
gracias

Answers

Answer:

Step-by-step explanation:

It’s 2

Answer:

[tex]1 + 1 = 2[/tex]

[tex]espero \: haberte \: ayudado[/tex]

The radius of the base of a cone is 4 inches. The slant height of the cone is
6 inches. Which is closest to the surface area of the cone?
F 75 sq in.
100 sq in.
H 126 sq in.
J 188 sq in.

Answers

Question:-

The radius of the base of a cone is 4 inches. The slant height of the cone is 6 inches. Which is closest to the surface area of the cone ?

Answer:-

Given:-

[tex] \bullet [/tex] Radius (r) of the base of a cone is 4 inches.

[tex] \bullet [/tex] Slant height (l) of the cone is 6 inches.

To Find:-

Which is closest to the surface area of the cone ?

Solution:-

We know,

Formula of surface area of a cone is πr(r + l) sq. units.

Taking value of π = 3.14

So, Surface area of the cone = 3.14 × 4(4 + 6)

Surface area of the cone = 12.56 × 10

Surface area of the cone = 125.6 sq. inches.

[tex] \because [/tex] 126 sq. inches is closest to 125.6 sq. inches.

So, option (H) 126 sq. in is correct. [Answer]

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Answer:

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Step-by-step explanation:

A

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[tex]4\pi {2}^{2} = 50.265482446[/tex]

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Answer:

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Step-by-step explanation:

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Step-by-step explanation:

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Step-by-step explanation:

I'll give a couple answers so you get the gist of things.

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Can somebody plz help tell me how to find the people who surveyed like where do u find it? Thx!

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How many people surveyed is just asking you how many people took the survey so count the total amount of tally marks you did

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Julius bought 4 boxes of plastic forks

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Answer:

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h

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p

e

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t

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l

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Answer:

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Answers

Answer:

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Step-by-step explanation:

Given equation is,

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Option E

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Answers

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C. X is the variable expression

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the two cities are 11.4 cm apart on the map

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Step-by-step explanation:

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Answers

Answer:

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__________________________

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Answers

Answer:

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Step-by-step explanation:

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Answers

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Step-by-step explanation:

I am not sure if you are aware of this but I am not sure if you are aware of the fact

Answer: x=-16/3

Isolate the variable by dividing each side by factors that don't contain the variable.
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