Pizza delivery. Suppose that the delivery time for a pizza delivery is Uniformly distributed between 15 to 20 minutes. Now suppose that 4 people from a dormitory independently order pizza from 4 different drivers (so the times for delivery are independent). What is the density of:
a. the minimum time until a pizza arrives?
b. the maximum time until a pizza arrives?
c. the time until the second pizza?
d. the time until the third pizza?