Night Shades Incorporated (NSI) manufactures biotech sunglasses. The variable materials cost is $1.85 per unit, and the variable labor cost is $3.7 per unit. a. What is the variable cost per unit? b. Suppose the company incurs fixed costs of $520,000 during a year in which total production is 286,000 units. What are the total costs for the year? c. If the selling price is $8.4 per unit, what is the NSI break-even on a cash basis? d. If depreciation is $143,000 per year, what is the accounting break-even point