The probability is 0.3 that a traffic fatality involves an intoxicated oralcohol-impaired driver or nonoccupant. In six trafficfatalities, find the probability that thenumber, Y, which involve an intoxicated oralcohol-impaired driver or nonoccupant is

a. exactlythree; at leastthree; at most three.

b. between two and four, inclusive.

c. Find and interpret the mean of the random variable Y.

d. Obtain the standard deviation of Y.