How do I solve this?

The local operations manager for the Internal Revenue Service must decide whether to hire one, two, or three temporary tax examiners for the upcoming tax season. She estimates that net revenues (000 dollars) will vary with how well taxpayers comply with the new tax code just passed by Congress, as follows. Show your work how you got your answer. NUMBER OF EXAMINERS One Two Three COMPLIANCE LOW NORMAL 50 50 100 60 150 70 HIGH 50 20 -10 (a) If she uses the Maximin criterion, how many new examiners will she decide to hire? (b) If she uses the minimax regret criterion, how many new examiners will she decide to hire? (c) If she feels the chances of low, medium, and high compliance are 20%, 30%, and 50% respectively, what are the expected net revenues for the number of assistants she will decide to hire? (d) If she feels the chances of low, medium, and high compliance are 20%, 30%, and 50% respectively, what is her expected value of perfect information (EVPI)