A cost accountant has derived the following data on the weekly output of standard size boxes from a factory.

Week	Output (thousands)	Total cost (thousand dollars)
1	20	60
2	2	25
3	4	26
4	23	66
5	18	49
6	14	48
7	10	35
8	8	18
9	13	40

(a) Determine the regression equation from which we can predict the total cost in terms of the weekly production. (4%)

(b) In the following week it is planned to produce 15,000 standard size boxes. Estimate the total cost of producing this quantity. (1%)

(c) Compute the linear correlation coefficient. Interpret the result.