Determine the minimum sample size required to be 99% confident that the sample mean driving distance to work is within 2 miles of the population mean driving distance to work. Use the population standard deviation from Exercise 2.

Data from Exercise 2;

The driving distances (in miles) to work of 30 people are shown in the table at the left. Assume the population standard deviation is 8 miles. 

Driving distances to work (in miles) 12 2 8 3 27 21 10 13 6 13 2 30 6. 1 10 2 12 16 18 4 3 13 6. 2 9