Each pair of glasses sold by company EYES has a warranty for 12 months. Suppose the life of a pair of glasses follows a normal distribution with mean 15 months and standard deviation 2 months. Please use probability distribution tables attached to solve the following problems.

(1) In the long run, what is the percentage of pairs of glasses that need repairs during the warranty period? (2) If we have a random sample of 300 pairs of glasses, what is the probability that more than 8% of batteries needing repairs during the warranty period?

(3) If we have a random sample of 10 pairs of glasses, what is the probability that the average glass life is longer than 16 months? (4) If we have a random sample of 10 pairs of glasses, the probability that the average glass life in the sample is longer than A months is 79.1%. Please find A.