5 A clock contains 4 new batteries each of which gives a voltage which is normally distributed with mean 1.54 volts and standard deviation 0.05 volts. The voltages of the batteries are independent. The clock will only work if the total voltage is greater than 5.95 volts.

1. Find the probability that the clock will work.
2. Find the probability that the average total voltage of the batteries of 20 clocks chosen at random exceeds 6.2 volts.