The number of people arriving for treatment at an emergency room can be modeled by a Poisson process with a rate parameter of si
x per hour. (a) What is the probability that exactly three arrivals occur during a particular hour? (Round your answer to three decimal places.)
(b) What Is the probability that at least three people arrive during a particular hour? (Round your answer to three decimal places.)
(c) How many people do you expect to arrive during a 15-min period?