How do you tell if a graph is a function

Can anyone me with 32,33,36,37,and 40.

Val and tony get paid per project. val is paid a project fee of $44 plus $12 per hour. tony is paid a project fee of $35 plus $15 per hour. write an expression to represent how much a company will pay to hire both to work the same number of hours on a project.

Evaluate each expression. determine if the final simplified form of the expression is positive or negative -42 (-4)2 42