A tire manufacturer believes that the tread life of its snow tires can be described by a Normal model with a mean of 32,000 miles and a standard deviation of 2500 miles. Complete parts d through e below.

d) Estimate the interquartile range (IQR) for these data. The IQR is enter your response here miles.

(Round to the nearest mile as needed.)

e) In planning a marketing strategy, a local tire dealer wants to offer a refund to any customer whose tires fail to last a certain number of miles. However, the dealer does not want to take too big of a risk. If the dealer is willing to give refunds to no more than 1 of every 20 customers, for what mileage can he guarantee these tires to last?

The tire dealer can guarantee these tires last at least enter your response here miles.

(Round to the nearest mile as needed.)