To help determine how many beers to stock the concession manager at Yankee Stadium wanted to know how the temperature affected beer sales. Accordingly, she took a sample of 10 games and recorded the number of beers sold and the temperature in the middle of the game.

x (temp.) Number of beers

80 20533

68 1439

78 13829

79 21286

87 30985

74 17187

86 30240

92 37596

77 9610

84 28742

a.Predict with 90% confidence the number of beers to be sold when temperature is 75 degrees.

b.Calculate and plot the residuals and predicted values of y.