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E19.2 (LO 1), AP Service In the month of June, Jose Hebert's Beauty Salon gave 4,0oo haircuts, shampoos, and hair colorings at an average price of $30 each. During the month, fixed costs were $16,800 and variable costs were 75% of sales. Compute contribution margin, break-even point, and margin of safety. Instructions a. Determine the contribution margin in dollars, per unit and as a ratio. b. Using the contribution margin technique, compute the break-even point in dollars and in units. c. Compute the margin of safety in dollars and as a ratio