Which of the following situations creates a voidable preference? [Assume that the debtor is insolvent, and that none of the transferees are insiders.]

1. On August 1, Debtor borrows $1,000 from Lender. The loan is unsecured. Debtor's sister repays the loan on September 1. Prior to that time, Debtor did not owe his sister anything. Debtor files for bankruptcy on October 1.

2. On June 1, Debtor buys a piece of equipment for $100,000 from Dealer. Debtor makes a $20,000 cash payment and finances the $80,000 balance with Dealer, who retains a security interest in the equipment. Dealer files its financing statement against the equipment on June 8. Debtor makes a $35,000 loan repayment to Dealer on July 15 and files for bankruptcy on August 7. The equipment has a value of $80,000.

3. On August 1, Debtor borrows $50,000 from Bank. The loan is unsecured. Debtor repays the loan on September 1 and files a bankruptcy petition on December 15.

4. On February 1, Debtor borrowed $10,000 from Finance Co. The loan is unsecured. On February 5, after a rough day for Debtor's stock price, Finance Co. insists on receiving collateral, and on February 8, Debtor granted to Finance Co. a security interest in its existing inventory and equipment (which had a value of greater than $20,000). Finance Co. filed its financing statement on February 9. Debtor filed a bankruptcy petition on April 25.