Given a half-life, explain how you calculate the value of an exponentially decaying quantity at any time t.

Choose the correct answer below.

A.

Let t be the amount of time that has passed and T half be the half-life. The quantity after time t is the original quantity times this factor of t12T half.

B.

Let t be the amount of time that has passed. The quantity after time t is the original quantity times this factor of 1/2t.

C.

Let t be the amount of time that has passed and T half be the half-life. The quantity after time t is the original quantity times this factor of T half 1/2 t/T half

D.

Let t be the amount of time that has passed. The quantity after time t is the original quantity times this factor of

1/2 T half /t