10. You want to open up a cust want to open up a custom skateboard shop. You can sell each skate- for $160. It takes 3 hours to make each skateboard. Each skateboard earns $25 per hour. Each skateboard costs $15 in raw materials. You estimate that your fixed costs are $20,000 per month. a. What is the contribution margin? b. How many skateboards must be sold each month in order to break even? c. What is the break-even dollar amount? d. How many skateboards must be sold to earn a $10,000 profit each month? e. What is your total monthly revenue if you want to earn a profit of $8,000