Skippy Quadcopters plans to sell a standard quadcopter (toy drone) for $54 and a deluxe quadcopter for $84. Skippy purchases the standard quadcopter for $34 and the deluxe quadcopter for $59. Management expects to sell two deluxe quadcopters for every three standard quadcopters. The company's monthly fixed expenses are $24,200. How many of each type of quadcopter must Skippy sell monthly to breakeven? To earn $13,200 ? First identify the formula to compute the sales in units at various levels of operating income using the contribution margin approach. (Abbreviations used: Avg.= average, and CM= contribution margin.) Next compute the weighted-average contribution margin per unit. First identify the formula labels, then complete the calculations step by step