A Geiger counter registers a count rate of 7,600 counts per minute from a sample of a radioisotope. Eighteen minutes later, the count rate is 1,900 counts per minute. What is the half-life of the radioisotope?

9 minutes is the half life of the radioisotope.

Step-by-step explanation:

Given;

initial count rate = 7,600 counts per minute

final count rate = 1,900 counts per minute

elapsed time, t = 18 minutes

The half life of the radioisotope is calculated as;

       Time (half life) remaining count rate

                     0  7,600 counts per minute

                      x 3,800 counts per minute

                     2x 1,900 counts per minute

thus, 2x = 18 minutes

x = 18 / 2

x = 9 minutes

Therefore, 9 minutes is the half life of the radioisotope.

which of the following can speed up the rate at which the liver breaks  

down alcohol?

question 1 options:

carbohydrates  

coffee  

nothing  

high-protein meals  

step-by-step explanation:

to determine the unit cost your would divide the total cost by the number sold.

7 bagels for $4.41       $4.41/7 = $.63 each at fresh side

5 bagels for $3.60         $3.60/5 = $.72 each at value mart