The Accounting Club wants to have a party for its members. The cost of renting space is $1,560, and the cost of refreshments will be $18 per person. Required: 1-a. What is the total cost if 400 people attend? 1-b. What is the average cost? (Round your answer to 2 decimal places.) 2-a. What is the total cost if 500 people attend? 2-b. What is the average cost? (Round your answer to 2 decimal places.)