The real estate office interviewed all persons age 16 and over in the sample households; there were 2,500 such persons. On the average, these 2,500 people commuted 7.1 miles to work, and the SD of the distances was 10.2 miles. (Again, if someone isn't working, the commute distance is defined to be 0; and all distances are one-way.) If possible, find a 95%-confidence interval for the average commute distance for all people age 16 and over in this town. If this isn't possible, explain why not.