Ron and Don make a written agreement for Ron to wash Don$$s car every week. They agree on price, schedule and payment terms. After Ron washed Don$$s car the first week, Don refused to pay because he claimed that Ron had agreed to wax the car as well. There is no mention of waxing in the written agreement. What is true?

Group of answer choices

Don must pay the value of the benefit received, but doesn$$t have to pay the full price because Ron did not wax the car.

Don must prove that Ron was supposed to wax the car by showing the notes he took during their negotiations.

Ron is under no obligation to wax the car, even if Ron and Don had discussed the possibility.

If waxing had been discussed, Ron must wax the car before he can get paid.