I need help with the following. Thank you!

2. David recently graduated with a B.A. in economics and was offered a job with a large company that pays $44,000 per year. At about the same time, David's grandfather died and left him an inheritance of $45,000. David decided to pass up the job, and using $39,000 from the inheritance, he purchased a tool rental business. (David put the other $6,000 into a savings account that pays 9 percent annual interest.) He put his full effort into the new business, and in the first three months of operation he had total sales revenue of $29,500 and total explicit costs of $14,260. a) What is David's accounting profit for the period? b) What is David's economic profit for the period? 3. Given the short run cost curves below answer the following questions) MC ATC AVC Costs 0 5 10 15 20 25 30 35 40 Quantity of outputa) At what output do diminishing returns begin? b) What is the most productive output? c) What is the economic capacity of the firm