Question

I NEED HELP ASAP!!!

The half-life of a certain radioactive material is 76 hours. An initial amount of the material has a mass of 439kg. How much radioactive material remains after 14 hours?
a) 0 kg
b) 0.163 kg
c) 0.652 kg
d) 386.377 kg

Answer 1

The formula for the amount of radioactive material remaining after a certain time can be expressed as:

N(t) = N₀ * (1/2)^(t/h)

Where:

N(t) is the amount of radioactive material remaining after time t

N₀ is the initial amount of radioactive material

h is the half-life of the material

Substituting the given values, we have:

N(14) = 439 * (1/2)^(14/76)

N(14) = 386.377 kg

Therefore, the amount of radioactive material remaining after 14 hours is 386.377 kg. The answer is option (d).

Explanation:

Answer 2

Use the radioactive decay formula: A = Ao*2^(-t/h), where

A = 722*2^(-17/71)

find 2^(-17/71) with a calc

A = 722*.847076

A = 611.59 kg after 17 hrs

Explanation: