1. To estimate the mean time that the customers spend in a privilegedlounge at an airport, the time for 35 randomly selected passengers ismonitored and the mean of this sample is 97 minutes and standarddeviationis 23 minutes.

a)Construct a 95% confidence interval for the mean time for all thepassengers.

b)Construct a 99% confidence interval for the mean time for all thepassengers.

c)Whichoftheseintervalsiswider?

2. Giventhatthepopulationstandarddeviation s=$275forthe expenses for the professional development activities by the employees of a LARGE company.How large a sample must be takento construct a confidence intervalfor the mean expenses for theprofessional development activities for all the employees with amarginof error ofno more than$25.00

a)witha90%confidence

b)witha95%confidence

c)witha99%confidence

3. A residential university system with 1000s of students takes a simplerandomsample of 357 students and asks them if they are satisfied with the quality ofstudentservices. If 71%ofthese357say"yes"

a)Construct a 95% confidence interval for the mean of all thestudentswho would say "yes."

b)What is the margin of error of the interval that you computed inthepart a)

C)Howlarge asamplemustbetakentoconstructa95% confidenceintervalforthispopulationproportionwithamarginof error ofno more than4%points