In fitting a least squares line to n = 20 data points, the following quantities were computed: SSxx = 60, SSyy = 225, SSxy = -75, x = 2.4, and y = 45.

a. Find the least squares line.

b. Graph the least squares line.

c. Calculate SSE.

d. Calculate s2.

e. Find a 90% confidence interval for b1. Interpret this estimate.

f. Find a 90% confidence interval for the mean value of y when x = 15.

g. Find a 90% prediction interval for y when x = 15.