Dorian charges his neighbor $8 per hour to walk the dog. His mom pays him $10 to wash her car. Part 1 (2pts): Define a variable (this means to pick a letter to use as your variable for this expression). Explain, in one sentence, why you chose the variable. Part 2 (3pts): Write an expression representing the total amount of money Dorian earns from walking the dog and washing his mom's car.