One more question

A sample of350 orders fortake-out food at a local pizzeria found that the average cost of an order was $29 with s=$13. (a) Find the margin oferror, if we use a95% confidenceinterval, for the average cost of an order. (b) Interpret for management the margin of error. (c) If weneed to be 99% confident, does the confidence interval become wider ornarrower? (d) Find the 99% confidence interval.