(10 pts) The lifespan of a car battery averages five years. Suppose the battery lifespan follows an exponential distribution. a. (3 pts) Find the probability that a randomly selected car battery will last more than three years. b. (3 pts) Find the variance of the battery lifespan. c. (4 pts) Suppose a three-year-old battery is still going strong. i. Find the probability the battery will last an additional five years. ii. How much longer is this battery expected to last?