4. You decide to buy a NYMEX WTI crude oil futures contract at the price of $86.92 per barrel. The contract represents 1,000 barrels of crude oil to be delivered three months from now. However, instead of paying the full value of the contract, you only deposit an initial margin requirement of 10%. A week later, the price of crude oil jumps to $90.21. a. What will be your profit or loss? b. What is your return from buying on margin? c. What would be your return had you invested the full amount