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最优财政政策要求税率随时间平稳变化,仅对政府支出的永久性变化作出反应。
没有事情是不可能的,“不可能”这个词本身就含有“不,可能”。
The Internet is for everyone.
The human mind is a set of information-processing machines that were designed by natural selection to solve adaptive problems faced by our hunter-gatherer ancestors.