假定与货币需求有关的物价水平包括进口产品的价格，而进口产品的价格取决于汇率。这就是说，货币市场可以表述

为：M/P=L(r，Y)。这里：P=λP_d+(1-λ)P_f/e，参数λ是物价指数P中国内产品的比例。假设国内产品价格P_d和用外国通货表示的外国产品价格P_f是固定的。

a．假定我们根据P_d与P_f给定的值(而不是通常所用的P)画出LM^*曲线。解释为什么在这个模型中这条LM^*曲线向右上方倾斜，而不是垂直的。

b．在这个模型中，在浮动汇率下，扩张性财政政策的影响是什么？请解释。与标准的蒙代尔—弗莱明模型进行对比。

c．假设政治不稳定提高了该国的风险贴水，从而使利率上升。在这个模型中，对汇率、物价水平和总收入的影响是什么？与标准的蒙代尔—弗莱明模型进行对比。

Suppose that the price level relevant for money demand includes the price of imported goods and that the price of imported goods depends on the exchange rate. That is, the money market is described by M/P=L(r，Y)，where P=λP_d+(1-_d)P_f/e. The parameter λ is the share of domestic goods in the price index P. Assume that the price of domestic goods P_dand the price of foreign goods measured in foreign currency P_fare fixed.

a．Suppose we graph the LM^*curve for given values of P_dand P_f(instead of the usual P). Explain why in this model this LM^*curve is upward sloping rather than vertical.

b．What is the effect of expansionary fiscal policy under floating exchange rates in this model？ Explain. Contrast with the standard Mundell-Fleming model.

c．Suppose that political instability increases the country risk premium and，thereby，the interest rate. What is the effect on the exchange rate, the price level, and aggregate income in this model？ Contrast with the standard Mundell-Fleming model.