Archer Daniels Midland decides to short 5 wheat futures contracts with each contract covering, 5,000 bushels of wheat for 283 cents per bushel in order to hedge its operation. The initial margin is $7, 200 per contract and the maintenance margin is $5, 400 per contract. What price change would lead to a margin call? Under what circumstances could $2, 850 be withdrawn from the margin account?