Jackson Co. makes and sells a single product. The current selling price is $15 per unit. Variable expenses are $9 per unit, and fixed expenses total $27,000 per month. (Unless otherwise stated, consider each requirement separately.)

1. Calculate monthly operating income (or loss) if a $2 per unit reduction in selling price results in a volume increase to 8,400 units per month.

2. Calculate the monthly operating income (or loss) that would result from a $1 per unit price increase and a $6,000 per month increase in advertising expenses, both relative to the original data. Assume a sales volume of 5,400 units per month.

3. Management is considering a change in the sales force compensation plan. Currently each of the firm's two salespeople is paid a salary of $2,500 per month.

4. Calculate the monthly operating income (or loss) that would result from changing the compensation plan to a salary of $400 per month, plus a commission of $0.80 per unit, assuming a sales volume of 6,000 units per month.

5. Calculate the monthly operating income (or loss) that would result from changing the compensation plan to a salary of $400 per month, plus a commission of $0.80 per unit, assuming a sales volume of 5,400 units per month.

6. Assuming that the sales volume of 6,000 units per month achieved in part 5 could also be achieved by increasing advertising by $1,000 per month instead of changing the sales force compensation plan. What would be the operating income or loss?