Armon, of Armon's Construction, called Ella, of Ella's Lumber and told her he needed 100 sheets of 4' x 8' grade A plywood. Ella agreed and the next day she delivered the plywood, and sent Armon the bill of $6,200, based on the market price of $62 per sheet, which is $11 more per sheet than the last time she ordered, two months earlier. Is there a valid contract they Ella can enforce if Armon does not pay? Explain all possibilities