1. An energy company changed its billing method in a small town claiming that the change would decrease the mean energy bill for customers. Under the old plan the mean monthly cost in the town was $225.To test the claim a sample of 47 energy bills were checked and the mean bill was $211 with a standard deviation of $89.Show all the steps and work to test the company's claim at the 5% significance level. You can use a theoretical distribution in stat key to get the p-value but do the problem out by hand.