1. Suppose that past history shows that 60% of college students prefer Brand C cola. A sample of 5 students is to be selected. The probability that exactly one prefers brand C is ________.

2. The actual voltages of power packs labeled as 12 volts are as follows: 11.77, 11.90, 11.64, 11.84, 12.13, 11.99, 11.77. Referring to the above, the critical t value for a 99% confidence interval for this sample is __________.

3.

The following table contains the probability distribution for X = the number of retransmissions necessaryr to successfully transmit a 1024K data packet through double satellite media. X 0 1 2 3 F 3.35 3.35 0.25 0.05 {X} The maximum number of retransmissions is