The half-life of a radioactive material is tH = 5.0 minutes. The initial amount of the material is 100.0 g. N = N0 e-kt or N = N0 (1/2)t/tH How much material remains after 8.0 minutes?
A. 29.0 g
B. 27.0 g
C. 33.0 g
How much time is required for the material amount to decrease to 15.0 g?
A. 12.4 minutes
B. 13.7 minutes
C. 11.8 minutes