Reports from a new system set up to monitor internet use by company employees indicate that 145 out of a random sample of 1100 employees at a corporation accessed internet sites that were clearly not related to their jobs over the last week. On average, employees who accessed non-job related sites spent 4.8 hours per week at such sites with a standard deviation of 2.1 hours.

(a) Give a 95% confidence interval for the percentage of employees at the corporationwho accessed non-job related sites.

(b) Statistics show that about 10% of people nationwide access non-job related sites at work. Is this company really any different from the national statistics?

(c) Can we say that roughly 95% of people at this company spent in the range of 4.8 hours plus or minus 4.2 hours on non-job related sites?