Mileage Tests Were Conducted on a Randomly Selected Sample of 100

Mileage tests were conducted on a randomly selected sample of 100 newly developed automobile tires. The average tread wear was found to be 50,000 miles with a standard deviation of 3,500 miles. What is the best estimate of the average tread life in miles for the entire population of these tires?

A) 50,000
B) 3,500
C) (50,000/100)
D) (3,500/100)
E) None of the choices are correct