Polonium-218 has a half-life of about 3 minutes.

after 15 minutes, how many milligrams of a 120 mg sample will remain?

a. 1.875 mg
b. 3.75 mg
c. 4.8 mg
d. 7.5 mg

Option B - 3.75 mg

Step-by-step explanation:

Given : Polonium-218 has a half-life of about 3 minutes.  

To find : After 15 minutes, how many milligrams of a 120 mg sample will remain?                                

Solution :

Considering an exponential model,

Where, y is the total amount

is the original amount

x is the half-life of Polonium-218

t is the time taken t=15 minutes

n is the time spent n=3 minutes

Substitute the values in the exponential model,

Therefore, Option B is correct.

3.75 mg is required amount.

(hint): the answer is in the question.

his answer is incorrect. i just used it, and it said it was incorrect. the answer is 0.