以下为上下文.
问题描述：
以下为上下文.
And here in the Midwest you have seen a boom in ethanol production and ethanol usage.And the reason why is,is that corn-based ethanol is leading an amazing change in the country.We consume about 5 billion gallons of ethanol right now in America.That's up nearly fivefold in a relatively quick period of time.The problem we face is that right now the most efficient way to make ethanol is through the use of corn
答
那在相当快的一段时期内上升了接近五倍.