On July 15, in a writing signed by both parties, Fixtures, Inc., agreed to deliver to Druggist on August 15 five storage cabinets from inventory for a total price of $5,000 to be paid on delivery. On August 1, the two parties orally agreed to postpone the delivery date to August 20. On August 20, Fixtures tendered the cabinets to Druggist, who refused to accept or pay for them on the ground that they were not tendered on August 15, even though they otherwise met the contract specifications. Assuming that all appropriate defenses are seasonably raised, will Fixtures succeed in an action against Druggist for breach of contract? 
Yes, because neither the July 15 agreement nor the August 1 agreement was required to be in writing.  Yes, because the August 1 agreement operated as a waiver of the August 15 delivery term.  No, because there was no consideration to support the August 1 agreement.  No, because the parol evidence rule will prevent proof of the August 1 agreement.