Suppose that past history shows that 60% of college students prefer Brand C cola. A sample of 5 students is to be selected.

1). The probability that exactly one prefers brand C is ________.

2). The probability that at least one prefers brand C is ________.

3). The probability that more than three prefer brand C is ________.

4). The average number that you would expect to prefer brand C is ______.

5). The variance of the number that prefer brand C is ________.