Problem 3. (18 points) The following data were collected for 12 months using a company's sales reports. The report shows, for each month, the amount of money the company spent for advertising (x) and the amount of sales (y) made after those advertising expenditures. Both the advertising and sales dollars are in units of thousand dollars. The Chief Executive Officer of the company is interested in the impact of the advertising spending on the actual sales. Month Y 1 52 4,670 58 5,310 69 6,320 4 75 7,050 5 83 8,210 6 82 7,100 778 6,590 65 6,140 9 54 4,640 10 41 3,850 11 32 3,280 12 42 4,050 2 3 8 a (a) Provide the scatter plot for advertising vs sales dollars with the trend line. (4 points) (b) Obtain a linear regression line for the data. (Hint: You need to calculate a and b to get the linear regression equation: y=a + bx) (8 points) (c) Predict the sales figures in months 13 and 14 if the advertising budgets allocated for months 13 and 14 are $50,000 and $55,000, respectively. (6 points)