As her senior project, Julie has decided to raise money for a charity by hosting a Spaghetti Dinner. In order to have the dinner, she had to borrow $100 to rent the hall from her parents (which they expect to get back). She is going to make $6 for every dinner purchased.

part A: Write an algebraic expression to describe the amount of money Julie will raise for any number of dinners purchased.

part B: Describe what the variable represents in this situation.