a) Consider the following data on the number of grandchildren in a random sample of 12 senior citizens residing in a retirement home: 12, 14, 11, 10, 9, 11, 13, 8, 9, 12, 12, 13 Compute the mean, median, mode, range and standard deviation of the data set b) A firm booked three hotels to provide accommodations for its clients. From past experience it is known that 20% of the clients are assigned rooms at Hotel A, 50% at Hotel B, and 30% at Hotel C. If the plumbing is faulty in 5% of the rooms at A, in 4% at B and in 8% of the rooms at C, what is the probability that a client will be assigned a room with faulty plumbing.