马上考了，请教问题在线等~~~

20.     (28411-!-item-!-188;#058&003617)

For years the beautiful Renaissance buildings in Palitito have been damaged by exhaust from the many tour buses that come to the city.  There has been little parking space, so most buses have idled at the curb during each stop on their tour, and idling produces as much exhaust as driving.  The city has now provided parking that accommodates a third of the tour buses, so damage to Palitito's buildings from the buses' exhaust will diminish significantly.

Which of the following, if true, most strongly supports the argument?

(A) The exhaust from Palitito's few automobiles is not a significant threat to Palitito's buildings.

(B) Palitito's Renaissance buildings are not threatened by pollution other than engine exhaust.

(C) Tour buses typically spend less than one-quarter of the time they are in Palitito transporting passengers from one site to another.

(D) More tourists come to Palitito by tour bus than by any other single means of transportation.

(E) Some of the tour buses that are unable to find parking drive around Palitito while their passengers are visiting a site.

我选D，应该是C.

First-time computer buyers buying PXC home computers typically buy models that cost much less and have a smaller profit margin per computer than do PXC computers bought by people replacing their computers with more powerful models.  Last year PXC's profits from computer sales were substantially higher than the previous year, although about the same number of PXC computers were sold and the prices and profit margins for each computer model that PXC sells remained unchanged.

If the statements above are true, which of the following is most strongly supported by them?

(A) PXC's competitors raised the prices on their computers last year, making PXC computers more attractive to first-time computer buyers.

(B) The number of people buying PXC computers who also bought PXC computer-related products, such as printers, was larger last year than the previous year.

(C) Among computer buyers who bought a PXC computer to replace their existing computer, the proportion who were replacing a computer made by a competitor of PXC was greater last year than the previous year.

(D) The proportion of PXC computers bought by first-time computer buyers was smaller last year than the previous year.

(E) PXC's production costs for its computers were lower last year than they had been the previous year.

我选B，应该是D.

34.     (31982-!-item-!-188;#058&005681)

For several years, per capita expenditure on prescription drugs in Voronia rose by fifteen percent or more annually.  In order to curb these dramatic increases, the ministry of health prohibited drug manufacturers from raising any of their products' prices.  Even though use of prescription drugs did not expand after this price freeze, per capita expenditure for prescription drugs continued to increase by a substantial percentage each year.

Which of the following, if true, most helps to explain why the ministry's action did not achieve its goal?

(A) After price increases were prohibited, drug manufacturers concentrated on producing new medications to replace existing products.

(B) The population of Voronia rose steadily throughout the period.

(C) Improvements in manufacturing processes enabled drug manufacturers to maintain high profit levels on drugs despite the price freeze.

(D) In addition to imposing a price freeze, the government encouraged doctors to prescribe generic versions of common drugs instead of the more expensive brand-name versions.

(E) After price increases were prohibited, some foreign manufacturers of expensive drugs ceased marketing them in Voronia.

我选E,应该是A.

我解释20 问题是汽车在路边等时和开车产生一样的废气，建一个停车常，使废气对建筑的损坏减少了，问支持，我觉得这里有个假设，就是在路边的废气对建筑有损害，而远离建筑的废气没有损坏或损害小

c说车的大部分时间其实是在等待，在路上走的时间是所有时间的１／４,而停车场使得汽车不停在路边，

d我觉得是无关的