Shenanigan's TV sells 13-inch televisions for $100. The unit variable cost per TV is $50 plus a selling commission of 10%. Fixed manufacturing costs are $1,250 per month, and fixed selling and administrative costs are $2,500. Required: a. What is the contribution margin per TV? b. What is the breakeven point in TVs? c. How many TVs must be sold to earn pretax income of $7,500