First of all, we need to consider what risks the United States is guarding against and whether the euro is going up or down.

From the topic, the euro rose later, that is to say, if you don't hedge after a few months, the cost in the United States will increase a lot. So, on March 5, June and September, the euro bought against the dollar = long.

(1.24700-1.22500) *1billion euros =2200000 euros.

(1.28860-1.26000) * 200 million euros =5720000 euros.

220000+5720000 = 7920000 euros

To put it simply, it cost 792W less, avoiding the cost increase brought by the rise of the euro in the later period.