In 2021, Cullumber Co. had break-even sales dollars of $ 825,000 based on a selling price of $ 10.0 per unit and fixed costs of $ 165,000. In 2022, the selling price and variable costs per unit did not change, but break-even sales dollars increased to $ 900,000. (a) Compute the variable cost per unit and the contribution margin ratio for 2021. (Round answers to 2 decimal places, e.g. 52.75.) Variable cost $ tA per unit Contribution margin ratio %