The Kernel Corporation, through its president, Demeter Gritz, requested from Vault Finance, Inc., a short-term loan of $100,000. On April 1, Gritz and Vault's loan officer agreed orally that Vault would make the loan on the following terms: (1) The loan would be repaid in full on or before the following July 1 and would carry interest at an annual rate of 15 percent (a lawful rate under the applicable usury law); and (2) Gritz would personally guarantee repayment. The loan was approved and made on April 5. The only document evidencing the loan was a memorandum, written and supplied by Vault and signed by Gritz for Kernel, that read in its entirety: "April 5 In consideration of a loan advanced on this date, Kernel Corporation hereby promises to pay Vault Finance, Inc., $100,000 on September 1.  Kernel Corporation  By /s/ Demeter Gritz  Demeter Gritz, President" Kernel Corporation did not repay the loan on or before July 1, although it had sufficient funds to do so. On July 10, Vault sued Kernel as principal debtor and Gritz individually as guarantor for $100,000, plus 15 percent interest from April 5. "At the trial, can Vault prove Kernel's oral commitment to repay the loan on or before July 1?
Yes, because the oral agreement was supported by an independent consideration.  Yes, because the evidence of the parties' negotiations is relevant to their contractual intent concerning maturity of the debt.  No, because such evidence is barred by the preexisting duty rule.  No, because such evidence contradicts the writing and is barred by the parol evidence rule