Question 3 (10 marks) The production manager of a company that manufactures car seas has been concerned about the number and cost of machine breakdowns. The problem is that the machines are old and becoming quite unreliable. However, the cost of replacing them is quite high, and the manager is not certain that the cost can be recouped given the slow economy. To help make a decision about replacement, he gathered data about last month's costs for repairs and the ages (in months) of the plant's 20 welding machines .................... Repairs Age 327.67 110 376.68 113 392 52 114 443.14 134 342.62 93 476.16 141 324.74 115 338.98 115 433.45 115 526.37 142 362.42 96 448.76 139 335 27 89 350.94 93 291.81 91 467.80 109 474.48 138 354.15 83 420.11 100 416.04 137 Tasks: a. Derive the simple linear regression equation. (2 Marks) b. Interpret the slope coefficient and the intercept coefficient (2 Marks) C. Calculate and interpret the Coefficient of Determination. (2 Marks) d. Calculate and interpret the correlation coefficient (2 marks) e. Predict the monthly repair cost of a welding machine that is 120 months old. (2 Marks)