Consider the following data set. Cl is years of education, C2 is years of jobexperience, C3 is age, and C4 is annual salary.

Row	Education	Experience	Ag	Salary
1	10	20	45	55139
2	10	5	23	48937
3	10	19	36	57624
4	11	15	50	58170
5	11	16	42	62202
6	11	8	30	51646
7	11	4	21	52563
8	12	10	34	49434
9	12	8	27	55153
10	12	18	38	63882
11	13	6	25	46067
12	13	10	46	60886
13	14	10	38	57190
14	14	2	22	52094
15	15	8	32	60620
16	16	5	49	59843
17	16	4	28	57288
18	17	7	33	67151
19	18	3	27	61313
20	19	3	32	64175

a. Estimate the relationship:

C4 = a + b(Cl)+c(C2)+d(C3)

b. Test the hypothesis that the entire model (C1, C2, and C3 combined) does not explain a significant amount of variation inthe dependent variable at the 5% level of significance.

c. What fraction of the variation in annual salary is explained by education, experience, and age?

d. Calculate a 90% Confidence Interval for expected income for a person with 12 years of education, 10 years of experience, and who is age 30.