Many companies are increasingly concerned about computer security and employees using their computers for personal use. a random sample of 50 employees of liberty mutual insurance company was asked whether they use the internet for nonbusiness (personal) purposes during the day. the number of hours for each employee is given on the text website. assume sigma = 0.5 hours. a. find a 95% confidence interval for the mean number of hours all employees at liberty mutual use the internet for personal reasons. b using the confidence interval in part (a), is there any evidence to suggest that the mean time spent using the internet for personal reasons is more than 1 our justify your answer. c. how large a sample is necessary for the bound on the error of estimation to be 0.1 hours? d. do you think the underlying distribution of time spent on internet for personal use is normal? explain your answer.