请教LSAT16III-1,14,18,24

albert

Those who support the continued reading and performance of Shakespeare's plays maintain that in England appreciation for his work has always extended beyond educated elites and that ever since Shakespeare's own time his plays have always been known and loved by comparatively uneducated people. Skepticism about this claim is borne out by examining early eighteen-century editions of the plays. These books, with their fine paper and good bindings, must have been far beyond the reach of people of ordinary means.
1. The main point of the argument is to
(A) suggest that knowledge of Shakespeare's play is a suitable criterion for distinguishing the educated elite from other members of English society
(B) provide evidence that at some time in the past appreciation for Shakespeare's play was confined to educated elites
(C) prove that early eighteenth-century appreciation for Shakespeare's works rested on aspects of the works that are less appreciated today
(D) demonstrate that since Shakespeare's time the people who have known and loved his work have all been members of educated elites
(E) confirm the skepticism of the educated elite concerning the worth of Shakespeare's plays
answer: B   why not D?


14. Although inflated government spending for weapons research encourages waste at weapons research laboratories, weapons production plants must be viewed as equally wasteful of taxpayer dollars. After all, by the government's own admission, the weapons plant it plans to reopen will violate at least 69 environmental, health, and safety laws. The government has decided to reopen the plant and exempt it from compliance, even though the weapons to be produced there could be produced at the same cost at a safer facility.
The reasoning in the argument is most vulnerable to criticism on which one of the following grounds?
(A) It offers no evidence that the "safer'" alternative production site actually complies with any of the jaws mentioned.
(8) It concedes a point regarding weapons research laboratories that undermines its conclusion about weapons production plants.
(C) It relies on evidence that does not directly address the issue of wasteful spending.
(D) It confuses necessary expenditures for research with wasteful spending on weapons
(E) It fails to establish that research laboratories and weapons production plants are similar enough to be meaningfully compared.
Answer: C   为什么？


18. In experiments in which certain kinds of bacteria were placed in a generous supply of nutrients, the populations of bacteria grew rapidly, and genetic mutations occurred at random in the populations. These experiments show that all genetic mutation is random.
Which one of the following, if true, enables the conclusion to be properly drawn?
(A) Either all genetic mutations are random or none are random.
(B) The bacteria tested in the experiments were of extremely common forms.
(C) If all genetic mutations in bacteria are random, then all genetic mutations in every other life form arc random also.
(D) The kind of environment in which genetic mutation takes place has no effect on the way genetic mutation occurs.
(E) The nutrients used were the same as those that nourish the bacteria in nature.
Answer: A  why not  B C D

Question24
When volcanic lava solidifies, it becomes uniformly magnetized in the direction in which the Earth's magnetic field points. There are significant differences in the direction of magnetization among solidified lava flows from different volcanoes that erupted at different times over the past several million years. Therefore, it must be that the direction of the Earth's magnetic field has changed over time. Since lava flows differing by thousands of years in age often have very similar directions of magnetization, the change in the direction of the Earth's magnetic field must take place very gradually over hundreds of thousands of years.
24. The argument that the direction of the Earth's magnetic field has changed over time requires the assumption that
(A) only lava can be used to measure the direction of the Earth's magnetic field as it existed in the distant past
(B) a single volcano can produce lava of differing consistencies during different eruptions
(C) not all solidified lava has changed the direction of its magnetization unpredictably
(D) there are fewer volcanic eruptions now than there were millions of years ago
(E) as lava flows down the side of a volcano, it picks up magnetized rocks
answer: C  为什么？

谢谢！

cranberry

1，文中明显的只提到18世纪，而D则根据这个事实得到了一个general的结论，所以不对。

2，文章的首句就说明要讨论的是浪费问题，可接下来的文字就偏离对浪费的讨论，开始说合规什么的，c指出了这一问题。

3，文中只说了一种细菌在某种条件下的基因变异，然后就得出所有的基因变异是随机的。B不对，因为此种细菌是否是普通的，不能作为一个得出general结论的依据，试想，人的基因突变和细菌一样吗？C的错误在于文中并未能证明是否所有的细菌的基因变异是随机的。D只说明环境对此种细菌的基因变异没有影响，同样不能解决细菌的基因变异和泛泛意义上的基因变异有和关系。

4，大前提是岩浆磁场和地球的磁场走向一致，小前提是许多岩浆的走向不一致，结论是地球的磁场走向变化了。我们测量岩浆的磁场是现在，这就要求在这许多年里，岩浆的磁场没有变化，或没有无法预期的变化。

albert

4.我想是不是因为原文 Since lava flows differing by thousands of years in age often have very similar directions of magnetization
所以(C) not all solidified lava has changed the direction of its magnetization unpredictably
理解对吗？
谢谢cranberry的帮助

pocahontas

LAVA FLOW这一题是NOT+WEAKEN型。取非后削弱，所以是必要条件，是前提。