He says some Asian currencies, including China's,are undervalued, but he says that steps to increase Asia's domestic demand will result in a gradual increase in their value.

VOA: standard.2009.11.13

Then go to the x equation and demand that this be equal to the desired x value and find the time.

然后列出关于 x 的方程,令这个式子等于给定的 x,并求出时间

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