Grocery retailier and UCC contracts/supplier contract

Scenario: Grocery, Inc., is a retail grocery store chain based in Any State, U.S.A. Grocery has stores throughout the United States. Grocery has written contracts with many different vendors to purchase the products they sell in their stores. Vendors range from individuals to international corporations. Tom Green works as the produce manager for the store in My Town, U.S.A. Jeff Fresh, 17 years old, is spending his summer vacation working for Tom in the produce department.
Questions:
Does Article 2 of the Uniform Commercial Code (UICC) apply to the contracts between Grocery and its vendors? Do common law contracts apply? Explain, in detail, why or why not. Also compare and contrast common law contracts and UICC Article 2 contracts.
In addition
Supplier, Inc., a large wholesaler, had a contract with Grocery. Supplier sued Grocery for breach of contract when Grocery failed to place an order for goods by a specific date as specified in the contract. Each order was to be worth at least $550. Grocery contended that the contract Bill Green signed was a standard preprinted supply contract without specifics regarding time of order and quantity. Green had authority to sign a standard supply contract, but could not authorize specific terms. This was unknown to Supplier. Supplier argued that the terms were "boilerplate" and could therefore be modified by acceptance. Supplier offered oral testimony at trial to prove that Green agreed to the modifications.
a) Is there a contract? If so, what are the terms?
b) Also, discuss the use of Supplier's oral testimony at trial.