Vaughn, Incorporated, sold 15,000 units last year for $180.00 each. Variable costs per unit were 554,00 for direct materials, $45,00 for direct labor, and $9.00 for variable ovethead. Fixed costs were $30.000 in manufacturing overhead and $18,000 in nonmanufacturing Required: a. What is the total contribution margin? b. What is the unit contribution margin? Note: Round your answer to 2 decimal places. c. What is the contribution margin rotio? Note: Round your intermediate colculations to 2 decimal places. d. If sales increase by 8,000 units, by how much will profits increase? Note: Round your intermediate calculations to 2 decimal ploces