18. Airline overbooking is a common practice. Many people make reservations on several flights due to uncertain plans and then cancel at the last minute or simply fail to show up. Eagle Air is a small commuter airline. Its planes hold only 15 people. Past records indicate that 20% of the people making a reservation do not show up for the flight. Let X denote the number of people making a reservation but do not show up for the flight out of 15 passengers. Assume X is a binomial random variable. What of the following statement is incorrect?
(A) On a given flight, the probability that all passengers have seats is $0.2^{15}$.
(B) The mean number of people making a reservation but do not show up for the flight equals 3.
(C) The mean number of people making a reservation and show up for the flight equals 12.
(D) The standard deviation of X equals 1.549.
(E) The variance of X equals 2.4.