Due to erratic sales of its sole producta high-capacity battery for laptop computersPEM, Inc., has been experiencing difficulty for some time. The company's contribution format income statement for the most recent month is given below: Sales (19,500 units at $30 per unit) $585,000 Variable expenses 409,500 Contribution margin 175,500 Fixed expenses 180,000 Net operating loss $(4,500) Refer to the original data. The Marketing Department thinks that a fancy new package for the laptop computer battery would help sales. The new package would increase packaging costs by 75 cents per unit. Assuming no other changes, how many units would have to be sold each month to earn a profit of $9,750