Can someone please help me with this problem

According to herman, one of the differences of managing a nonprofit versus a for-profit corporation is

The retained earnings account has a credit balance of $24,650 before closing entries are made. if total revenues for the period are $77,700, total expenses are $56,900, and dividends are $13,050, what is the ending balance in the retained earnings account after all closing entries are made?

The school cafeteria can make pizza for approximately $0.30 a slice. the cost of kitchen use and cafeteria staff runs about $200 per day. the pizza den nearby will deliver whole pizzas for $9.00 each. the cafeteria staff cuts the pizza into eight slices and serves them in the usual cafeteria line. with no cooking duties, the staff can be reduced by half, for a fixed cost of $75 per day. should the school cafeteria make or buy its pizzas?