Dorothy Kelly sells life insurance for the Prudence Insurance Company. She sells insurance by making visits to her clients homes. Dorothy believes that the number of sales should depend, to some degree, on the number of visits made. For the past several years, she kept careful records of the number of visits (x) she made each week and the number of people (y) who bought insurance that week. For a random sample of 15 such weeks, the x and y values follow. x 10 20 18 15 28 5 20 14 22 7 15 29 8 25 16 y 4 12 8 5 8 2 5 6 8 3 5 10 6 10 7 In this setting we have Σx = 252, Σy = 99, Σx2 = 4998, Σy2 = 761, and Σxy = 1889. (g) Find a 90% confidence interval for the number of sales Dorothy would make in a week during which she made 21 visits. (Round your answers to one decimal place.) lower limit sales upper limit sales