Doc Jones owns Doc's coffee shop, and his accountant has told him that his total fixed costs to run his business in a very nice upscale business-oriented neighborhood, excluding his salary, are $15,000 per month. Doc is in competition with a Seattle's coffee shop just down the block. Consequently, his prices are about the same as theirs. He has calculated that the average cup of coffee cost him $1.87 cents, which includes the coffee, the cup and condiments, such as sugar, sweetener, creams, napkins, and stir sticks. His average selling price is $4.85 per cup. He currently sells 8,000 cups of coffee per month. Doc has figured that if he lowers his price by $1.00 per cup, he would increase his sales to 11,000 cups per month and make more money. The amount he would increase his earnings is:

(20 points) a bank has been receiving complaints from real estate agents that their customers have been waiting too long for mortgage confirmations. the bank prides itself on its mortgage application process and decides to investigate the claims. the bank manager takes a random sample of 20 customers whose mortgage applications have been processed in the last 6 months and finds the following wait times (in days): 5, 7, 22, 4, 12, 9, 9, 14, 3, 6, 5, 15, 10, 17, 12, 10, 9, 4, 10, 13 assume that the random variable x measures the number of days a customer waits for mortgage processing at this bank, and assume that x is normally distributed. 2a. find the sample mean of this data (x ě…). 2b. find the sample variance of x. find the variance of x ě…. for (c), (d), and (e), use the appropriate t-distribution 2c. find the 90% confidence interval for the population mean (îľ). 2d. test the hypothesis that îľ is equal to 7 at the 95% confidence level. (should you do a one-tailed or two-tailed test here? ) 2e. what is the approximate p-value of this hypothesis?