The tread life of a type of tire produced by Tough Tires is a random variable best described by a normal distribution with a mean of 60,000 miles and a standard deviation of 1400 miles.

a.What percentage of this type of tire will last between 56,000 miles and 57,000 miles?Round your answer to the nearest tenth of a percent.

b.If the owner of Tough Tires is willing to replace 1.5% of tires that wear out, what should the warranty be for the number of miles the tire should last?Round your answer to the nearest mile.