In September, Carla Vista Industries sold 840 units of product. The average sales price was $50. During the month, fixed costs were $8,310 and variable costs were 70% of sales. (a) Determine the contribution margin in dollars, per unit, and as a ratio. (Round Contribution margin to 0 decimal places, eg. 5,275. Other all answers to 2 decimal places, eg. 52.75) Contribution margin (in dollars) $ Unit contribution margin $ Contribution margin ratio %6