The first question should be to make up the deposit of 750, because you have accumulated losses of 750 yuan on July 4th, and the maintenance deposit is 50% of the initial deposit, that is, 500 yuan. As long as the margin balance on your book is lower than the maintenance margin, you must make up for the loss and prevent the forced liquidation. This maintenance margin is only a minimum margin level relative to the extreme unfavorable state, and the margin must be replenished to the initial reserve level when the extreme unfavorable state occurs.

According to the above statement, the second question can be calculated. The contract is based on 100 pounds of gold (the problem is two gold futures contracts), the margin is 5% of the underlying assets, and the maintenance margin level is 75%. That is to say, the maintenance margin level of the two gold futures contracts is not less than 3000, and the cumulative loss in June 1 kloc-0/day is/kloc. Therefore, the margin added at this time is 1340, and on June 17, the accumulated loss at this time is 2,600 because the margin has been added once before, so subtracting the accumulated loss at this time from the last added 1340 is the amount of margin that should be added this time.