Variable Cost Concept of Product Pricing Voice Com, tnc., produces and selts cellular phones. The costs of producing and selling 3,500 units of celliular phones are as follows: Voice Com desiren a profit equal to a 15% rate of raturn on invested assets of 5595,000. Assume that Voice Com, Inc, uses the variable cost concept of applying the cost-plus approach to product pricing. a. Determine the variable costs and the veriable cost amount per unit for the production and sale of 3,500 units of cellular phones. b. Determine the variable cost markup percentage for cellular phones. c. Determine the selling price of cellular phones. Round to the nearest cent. per phone