A doctor prescribes 200.0 mg of a drug that decays by 25% each hour. What is the half-life of the drug?
A. 145 minutes
B. 133 minutes
C. 120 minutes
How much drug remains after a time of 3 hours?
A. 84.3 mg
B. 50.0 mg
C. 75.2 mg
How much time is required for the mass of drug to decrease to 10.0 mg?
A. 625 minutes
B. 565 minutes
C. 500 minutes