题目：
It is April 15, and a trader is entered into a short position in two soybean meal futures contracts. The contracts expire on August 15, and call for the delivery of 100 tons of soybean meal each. Further, because this is a futures position, it requires the posting of a $ 3000 initial margin and a $1500 maintenance margin per contract. For simplicity, however, assume that the account is marked to market on a monthly basis. Assume the following represent the contract delivery prices (in dollars per ton) that prevail on each settlement date:
A．April 15 (initiation)
B．173.00
C．May 15
D．179.75
E．June 15
F．189.00
G．July 15
H．182.50
I．August 15 (delivery)
J．174.25
答案：
参考答案：C
解析：Use the following steps to calculate the margin account balance as of May 15. At initiation: (Beginning Balance, April 15) Initial margin×number of contracts=3000×2=6000; Maintenance margin×number of contracts=1500×2=3000. As of May 15: (Ending contract price per ton-beginning contract price per ton)×tons per contract×contracts=(179.75-173.00)×100×2=1350. Since the trader is short, this amount is subtracted from the beginning margin balance, or 6000-1350=4650.
