To study short term effects of smoking, a sample of 100 smokers was drawn. Each person was asked to report the average number of cigarettes smoked per day and the number of days absent from work due to health reasons. A regression model was used to study the relationship between numbers of cigarettes smoked on number of days absent from work due to health reasons. UseSmoking3.xlsx for your analysis.

Data shown below -

Cigarettes	Days
43	19
41	18
47	22
46	18
46	20
45	18
45	15
44	18
42	12
42	15
42	9
40	13
49	19
48	22
48	20
47	18
47	14
47	22
46	18
45	21
45	13
45	20
45	15
44	17
44	14
44	25
44	14
43	15
43	13
43	20
43	14
42	24
42	14
42	14
42	18
41	17
41	15
41	12
41	12
41	9
41	16
41	16
40	14
40	12
40	24
40	15
40	14
39	17
39	17
38	15
37	19
37	18
37	19
37	20
37	14
37	13
36	10
36	17
36	12
36	14
35	14
35	9
35	18
35	10
34	14
34	14
34	15
34	9
33	13
32	12
32	10
32	15
31	14
31	11
31	8
30	11
30	12
30	9
30	14
29	9
29	15
29	14
28	14
28	15
28	14
27	14
27	8
26	6
26	11
25	14
25	3
24	15
22	9
20	8
19	9
17	7
17	12
17	10
16	5
15	7

If, on average, a person smokes 10 cigarettes a day, on average how many days would you expect that person to be absent from work? (Please round your answer to at least two decimal places.)
What is the correlation coefficient between the number of cigarettes and the number of days absent from work?
What percentage of variation in number of days absent from work is explained by the number of cigarettes each smoker smokes?
What is the standard deviation of prediction errors for this model?