Calculate gross pay in the following cases- a) Mark works at a rock concert selling programs. He is paid $20 for showing up, plus 25 cents for each program that he sells. He sells 175 programs. How much does he earn working at the rock concert? b) Savannah works as an electrician and earns $36.50/hr. If it takes her 25 hours to completely wire a basement, how much will she earn? d) Calculate the commission pay for the following: Jill a real estate agent sold a house for $95,000 she will earn 25% for the sale. What is her commission pay?