A tire manufacturer believes that the tread life of its snow tires can be described by a Normal model with a Approximately what percent of these snow tires will last between 30,000 and 35,000 miles? mean of 32,000 miles and a standard deviation of 2500 miles. Calculate z Shade and mark area under curve t. If you buy a set of these tires, should you hope they'll last 40,000 miles or more? Calculate 2 Shade and mark area under curve Approximately what percent of these snow tires will last less than 30,000 miles? Calculate z Shade and mark area under curve A dealer wants to offer a refund to customers whose snow tires fail to reach a certain number of miles, but he can only offer this to no more than 1 out of 25 customers. What mileage can he guarantee? Calculation