PB.9 A motel has a rooms department and a dining room, and total fined cost of the operation is $335,000. Annual sales revenue and cost figures are as follows Sales revenue Variable costs Contribution margin $440,000 $110,000 32.000) 66,000) 198,000) 08.00 S 44,000 $352,000 a. What will be the increase in contribution margin if there is a $20,000 b.What will be the increase in contribution margin if there is a $20,000 c. If we want to double the current operating income be fore tax with vari- d. If we want to double the curnent total operating income before tax with increase in sales revenue only in the rooms department? increase in sales revenue only in the food department? able costs remaining the same and covering fixed costs, what increase in room sales revenue is needed? direct costs remaining the same and covering fixed costs, what increase in food sales revenue is needed? e. If we want to double the curnent operating income before tax with di- rect costsmaining the same, what will increase in sales revenue have to be if the increase is provided jointly by both departments combined? Assume sales revenue ratios stay as originally stated