According to the U.S. Census Bureau, in 2007 about 10% of persons between 25 and 30 years old live alone. For a random sample of size n, use the binomial table to find the probability of

(a) 1 or fewer persons living alone when n =

12.

(b) 2 or more persons living alone when n =

12.

(c) Find the expected number when n = 12.

(d) 1 or fewer persons living alone when n =

20.