Tucson Machinery, Inc., manufactures numerically controlled machines, which sell for an average price of $0.5 million each. Sales for these NCMs for the past two years were as follows: Use Exhibit 18.10. LAST YEAR THIS YEAR QUARTER QUANTITY (UNITS) QUARTER QUANTITY (UNITS) I 13 I 19 II 19 II 25 III 27 III 29 IV 17 IV 20 a. Find the equation of a simple linear regression line using Excel. (Round your answers to 3 decimal places.) b. Compute trend and seasonal factor from a linear regression line obtained with Excel. (Do not round intermediate calculations. Round your answers to 3 decimal places.) c. Forecast sales for next year using the above seasonal factors. (Do not round intermediate calculations. Round your answers to 2 decimal places.)