Telephone calls to the national reservation center for motels were studied. A certain model defined a Type I call to be a call from a motel's computer terminal to the national reservation center. For a certain motel, the number, X, of Type 1 calls per hour has a Poisson distribution with parameter 1 = 1.5. Answer the following questions. a. Determine the probability that the number of Type 1 calls made from this motel during a period of 1 hour will be exactly two. The probability that exactly two Type 1 calls are made is (Do not round until the final answer. Then round to four decimal places as needed.) b. Determine the probability that the number of Type 1 calls made from this motel during a period of 1 hour will be at most two. The probability that at most two Type 1 calls are made is (Do not round until the final answer. Then round to four decimal places as needed.) c. Determine the probability that the number of Type 1 calls made from this motel during a period of 1 hour will be at least four. (Hint: Use the complementation rule.) The probability that at least four Type 1 calls are made is (Do not round until the final answer. Then round to four decimal places as needed.) d. Find the mean of the random variable X. HE e. Find the standard deviation of the random variable X.