Rose, a minor, bought a new Buick Riviera from Sheehan Buick. Seven months later, while still a minor, he attempted to disaffirm the purchase. Sheehan Buick refused to accept the return of the car or to refund the purchase price. Rose, at the time of the purchase, gave all the appearance of being of legal age. The car had been used by him to carry on his school, business, and social activities. Can Rose successfully disaffirm the contract? Why or why not?