What level of output must firm produce to maximize profits

Question

A perfectly competitive firm has the following fixed and variable costs in the short run. The market price for the firm's product is $140.

            Output               FC                   VC              TC             TR     Profit/Loss

              0                      $90               $    0               ___           ___           ___

         1                                            90                90             ___           ___       ___

         2                                            90               170           ___           ___       ___

         3                                            90               290           ___           ___       ___

         4                                            90               430           ___           ___       ___

         5                                            90               590           ___           ___       ___

         6                                            90               770           ___           ___       ___

a. Complete the table.

b. What level of output should the firm produce to maximize profits?