Use Excel to answer the following questions and submit to the Submission Folder. Question 1. Diana Company, a sole proprietorship, sells only one product. The regular price is $160. Variable costs are 55% of this selling price, and fixed costs are $8,400 a month. Management decides to decrease the selling price from $160 to $145 per unit. Assume that the cost of the product and the fixed operating expenses are not changed by this pricing decision. Required: Answer the following questions: A. At the original selling price of $160 a unit, what is the contribution margin ratio? B. At the original selling price of $160 a unit, what dollar volume of sales per month is