一国目前以每辆8000美元的价格进口汽车。该国政府认为，经过一段时间后，国内生产者能够以6000美元的成本生产

汽车。但是，在国内生产的初始尝试阶段，每辆汽车的生产成本达到10000美元。

a．假设每个试图生产汽车的企业都必须经过高成本的尝试生产阶段。在什么情形下，较高的起步成本能够证明保护幼稚工业是合理的？

b．现在假设相反的情形，一旦企业A承担了学习成本，学会了如何以6000美元的成本生产汽车，那么其他企业就能够模仿并达到同样的水平。试解释上述情形是怎样阻碍国内工业发展的，对幼稚工业进行保护有助于避免这种情形吗？

A country currently imports automobiles at ＄8000 each．Its government believes domestic producers could manufacture autos for only ＄6000 given time but that there would be an initial shakedown period during which autos would cost ＄10,000 to produce domestically．

a．Suppose that each firm that tries to produce autos must go through the shakedown period of high costs on its own．Under what circumstances would the existence of the initial high costs justify infant industry protection？

b．Now suppose，on the contrary，that once one firm has borne the costs of learning to produce autos at ＄6000 each，other firms can imitate it and do the same．Explain how this can prevent development of a domestic industry，and how infant industry protection can help．