Assume that a plan is set at OK to require classes to meet either three or four days a week in order to make better use of classroom facilities because currently, classrooms sit empty on Friday afternoons and evenings and on Saturdays. However, some are concerned that this proposal will put a hardship on the commuter students because it will require more driving to/from campus. OK, officials want to estimate the average number of miles driven, one way, to campus by the commuter students. It is estimated that some students drive as little as 0 miles to campus while at least one student reported driving one way as far as 60 miles. OK, officials want to be 95% confident that the sample mean is no more than +/- 2 miles from the real average number of miles driving in the population.

1. What is the required sample size?
2. After the study is conducted, we learn that the standard deviation in the sample data - which is now our best estimate of "s" - is actually 12.3. What impact does this new measure of variation have on the estimated mean number of miles driven?