According to the website www.zanebenefits.com, the average cost of a stay in a U.S. hospital in 2013 for a Medicare patient was $11,600. Assume that this cost is exponentially distributed.

a. Determine the probability that a randomly selected patient’s stay in an American hospital will cost more than $14,000.
b. Calculate the probability that a randomly selected patient’s stay in an American hospital will cost less than $9,000.