Olivia drinks an 8 oz cup of coffee that has 95 mg of caffeine in it. Caffeine has a half- life of about five hours. This means that every five hours, the amount of caffeine remaining in the body is reduced by half.

A. How much caffeine will still be in Olivia's system after 5 hours? After 10 hours?

B. How much caffeine will still be in Olivia's system after 12 hours?

C. What proportion of caffeine remains in the body each hour?