Show your complete work

4. (SHOW YOUR COMPLETE WORK) A hardware store sold 200,000 units of a product at $5 per unit in November, and sold 205,000 units of the same product at $4.75 per unit in December. The store has 9 full-time employees and each employee works 48 hours per week. In the month of November, the store also had 4 part-time employees and each part-time employee worked 18 hours per week. In the month of December, the store also had 3 part-time employees and each part-time employee worked 20 hours per week. Assume that there are 4 work weeks in each month. a. Find the labor productivity (expressed in sales dollars earned per labor-hour) for the month of November. [7 points] b. Find the labor productivity (expressed in sales dollars earned per labor-hour) for the rionth of December. [7 points] c. Find the percentage change in labor productivity from November to December. [2 points]