We saw in a review exercise in Chapter 4 on Calculating the Derivative that driver fatality rates were highest for the youngest and oldest drivers. When adjusted for the number of miles driven by people in each age group, the number of drivers in fatal crashes goes down with age, and the age of a randomly selected driver in a fatal car crash is a random variable with probability density function given by ƒ(t) = 0.06049e^-0.03211t for t in [16, 84]. Find the following probabilities of the age of such a driver.

(a) Less than or equal to 25
(b) Greater than or equal to 35
(c) Between 21 and 30
(d) Find the cumulative distribution function for this random variable.
(e) Use the answer to part (d) to find the probability that a randomly selected driver in a fatal crash is at most 21 years old.