if the city council institutes new parking regulations,city revenue will sureluy increase. Since studies have conclusively shown that, if such parking regulations are put into effect, there is an increase in parking violations, and an increase in parking violations will result in a reater number of parking fines collected.

如果以上对,以下哪个也对.

c. the city council will institute ne parking regulations only if an increase in city revenues can be expected to result.为什么不对？

d. if the city council's new regulations cause more parking violators to be ticked, the city revenue will increase.正确答案

33. A certain viral infection is widespread among children, and about 30 percent of children infected with the virus develop middle ear infections, antibiotics, although effective in treating bacterial infections, have no effect on the virus. Yet when middle ear infections in children infected with the virus are treated with antibiotics. The ear infections often clear up. Which one of the following most helps to explain the success of the treatments with antibiotics? A.Although some types of antibiotics fail to clear up certain infections, other types of antibiotics might provide effective treatment for those infections. B.Children infected with the virus are particularly susceptible to bacteria that infect the middle ear. C.Many children who develop middle ear infections are not infected with the virus. D.Most viral infections are more difficult to treat than are most bacterial infections. E.Among children not infected with the virus, fewer than 30 percent develop middle ear infections. 我觉得A对，不过不知道正确答案。

然而当用抗生素治疗由病毒引起的中耳炎的儿童时。 中耳炎经常会消除（治愈）

B说 B.Children infected with the virus are particularly susceptible to bacteria that infect the middle ear. 病毒引起的发炎，特别地会发展成细菌，感染中耳。(结果是导致中耳炎)