Tim's Bicycle Shop sells 21-speed bicycles. For purposes of a cost-volume-profit analysis, the shop owner has divided sales into two categories, as follows: Product Type High-quality Medium-quality Sales Price Invoice Cost $2,000 1,100 Sales Commission $1,050 $110 270 40 Three-quarters of the shop's sales are medium-quality bikes. The shop's annual fixed expenses are $239,400. (In the following requirements, ignore income taxes.) Required: 1. Compute the unit contribution margin for each product type. 2. What is the shop's sales mix? 3. Compute the weighted-average unit contribution margin, assuming a constant sales mix. 4. What is the shop's break-even sales volume in dollars? Assume a constant sales mix. 5. How many bicycles of each type must be sold to earn a target net income of $128,250? Assume a constant sales mix.