Borachio eats at the same fast food restaurant every day. Suppose the time X between the moment Borachio enters the restaurant and the moment he is served his food is normally distributed with mean 4.2 minutes and standard deviation 1.3 minutes.

Find the probability that when he enters the restaurant today it will be at least 5 minutes until he is served.

Find the probability that average time until he is served in eight randomly selected visits to the restaurant will be at least 5 minutes.