Question 2 [18] Suppose that a sample of size 10 was collected to study the relationship between x and y. From the sample data, the following information was obtained. Xi ei 23 4 7 3 -2 10 0 12 -2 15 18 -7 -3 20 3 21 25 -2 7 i = -3.18+ 2.49x (a) Use a t-test approach to determine whether or not there is a significant relationship between x and y at 10% level. (b) Construct and interpret 90% interval estimate of E(y) at x6 (c) Find the standard error of the point estimator of the model intercept