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.

109 trust me

step-by-step explanation:

15%

step-by-step explanation:

use the table and count the number of guesses that has two correct answers.

the following are two correct answers

10010, 01100, 11000

a total of 3 numbers having 2 correct guesses out of 20 questions.

probability of getting 2 correct guesses = the number of questions getting 2 correct answers / total number of questions.

= 3/20

to convert it into percent multiply by 100, we get

= 3/20 * 100

= 15%

the answer is 15%

you.