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Bob Newhart operates a bed and breakfast hotel in Vermont. Bob employs his longtime friend George Utley a caretaker all around fixit expert at an annual salary of $28,000. In addition, Bob employs college student Stephanie Vanderkellen who oversees housekeeping details at an annual salary of $20,000. A gourmet breakfast for guests at the hotel is provided by Larry, Darrell and Darrell an annual cost of $23,000. Real estate taxes are $8,825 per year, and depreciation on the hotel is $5,175 per year. The rooms rent at an average price of $49 per person per night including breakfast. Other costs are laundry and cleaning service at a cost of $3 per person per night and the cost of food which is $6 per person per night. Required: (a) Determine the number of rentals and the sales revenue Bob needs to breakeven using the contribution margin technique. (b) If the current level of rentals is 4,250, by what percentage can rentals decrease before Bob has to worry about having a net loss? (c) Bob is considering upgrading the breakfast service to attract more business and increase prices. This will cost an additional $4 for food costs per person per night. In addition, annual fixed costs will increase by $3,000. Bob's wife Joanna feels she can increase the room rate to $63 per person per night. Determine the number of rentals and the sales revenue Bob needs to breakeven if the changes are made