Speculation with a futures contract

Before any trading, George begins with a margin account balance of $0. On May 1, George believes that silver will appreciate in the next 4 days. On May 1, George takes a long position in a futures contract for silver with a futures price of $10/ounce. Each contract is for 1000 ounces of silver. The initial margin is $3000 and the maintenance margin is $2500. On May 2, the settlement futures price is $9.80/ounce. On May 3, the settlement futures price is $9.10/ounce. On May 4, George offsets with a futures contract with a futures price of $9.40/ounce. Note that all contracts are for silver with delivery date of May 25.After George offsets on May 4, what is his margin account balance?

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