1. Fill in the blanks in the following table to answer the questions below. (1) (2) (3) (4) (5) (6) Level of Total benefit Total cost Net benefit Marginal Marginal of activity of activity of activity benefit cost (A) (TB ITC INB [MB) (MC) $0 $0 $0 15 30 40 11 48 20 54 30 58 45 61 61 63 80 IIIIIIII IIIIIIIII a. What is the optimal level of activity in the table above? b. What is the value of net benefit at the optimal level of activity? c. Can net benefit be increased by moving to any other level of A? Explain