LSAT2-2-16 B为何不对/L2-2-18答案到底是B是C？

flyingceleste

LSAT-2-16The advanced technology of ski boots and bindings has brought a dramatic drop in the incidence of injuries that occur on the slopes of ski resorts: from 9 injuries per 1,000 skiers in 1950 to 3 in 1980. As a result, the remainder of ski-related injuries, which includes all injuries occurring on the premises of a ski resort but not on the slopes, rose from 10 percent of all ski-related injuries in 1950 to 25 percent in 1980. The incidence of these injuries, including accidents such as falling down steps, increases with the amount of alcohol consumed per skier.

16. Which one of the following can be properly inferred from the passage?

(A) As the number of ski injuries that occur on the slopes decreases, the number of injuries that occur on the premises of ski resorts increases.

(B) The amount of alcohol consumed per skier increased between 1950 and 1980.

(C) The technology of ski boots and bindings affects the incidence of each type of ski-related injury.

(D) If the technology of ski boots and bindings continues to advance, the incidence of ski-related injuries will continue to decline.

(E) Injuries that occurred on the slopes of ski resorts made up a smaller percentage of ski-related injuries in 1980 than in 1950.

答案是E，不太明白，B为何不对，原文不是提到The incidence of these injuries, including accidents such as falling down steps, increases with the amount of alcohol consumed per skier.

拿说明the more alcohol the more incidence of injuries，why not E ？puzzled

18. Learning how to build a nest plays an important part in the breeding success of birds. For example, Dr. Snow has recorded the success of a number of blackbirds in several successive years. He finds that birds nesting for the first time are less successful in breeding than are older birds, and also less successful than they themselves are a year later. This cannot be a mere matter of size and strength, since blackbirds, like the great majority of birds, are fully grown when they leave the nest. it is difficult to avoid the conclusion that they benefit by their nesting experience.

Which one of the following, if true, would most weaken the argument?

(A) Blackbirds build better nests than other birds.

(B) The capacity of blackbirds to lay viable eggs increases with each successive trial during the first few years of reproduction.

(C) The breeding success of birds nesting for the second time is greater than that of birds nesting for the first time.

(D) Smaller and weaker blackbirds breed just as successfully as bigger and stronger blackbirds.

(E) Up to 25 percent of all birds are killed by predators before they start to nest.

这题看到以前的讨论说选C，但答案是B，到底哪个正确呀，但即使是B还是没搞懂，该题讨论的是breeding success and nestding experience 之间的关系，与生蛋有何相关呀

[此贴子已经被作者于2005-1-26 0:55:47编辑过]

hedonism555

16,  A basic concept,   percentage is not same to absolute number.

So, the percentage increase of remainder is not same to a corresponding increase in overall incidences.

Since slope injuries, another contributing part of all injuries, declined in percentage, it is highly possible that remainder increased its percentage on the overall without actual committing more incidences.

Inaddition, the last sentense used the verb "increases" not "increased" to suggest a general situation instead of an established fact.

Thus, B is wrong in that the postulated increase of alcohol consumption is not well supported by any legitimate evidence.

E, quite abvious, in 1950 ,  it is 9/1000,   in 1980, it is 3/1000,  regardless how overall number changed during the period, the percentage slumped.

18,  hehe, it definately has a direct relation with laying eggs. The more viable eggs( those can develop into baby brid), the more successful cases of breeding.

So, B provide an explanation that it is the initial small number of viable eggs, not the nesting experience, in causing the lower rate of breeding at the first time of nesting.

C totally functions a contradictary role.  It is not weakening but support since the second time of nesting will definately gain more experience than the first time. So, it justifies the conclusion that skill or experience of nesting contributed the success of breeding.

lay eggs not = breeding or reproduction

breeding and reproduction = have the boby born out.

20,  it is a confusion between sufficient condition and necessary condition.

A= saving account   B = interest bearing account

all A is B = If A , then B.  A is a sufficient condition to B.  from A,  can get B, but from B, cannot get A.

So, just imagine interest-bearing account is a larger group that includes all saving accounts and other types. If there are some tax-free in interest-bearing accounts, we cannot be sure they will fall into the saving account category.

If the first sentence is modified into "all interest-bearing accounts are saving account" , then this question is ok.

A states that being an artist is sufficient condition to be intellectual, then any one satisfying this will be qualified. nothing wrong.

Clear?

[此贴子已经被作者于2005-1-26 1:42:24编辑过]

flyingceleste

哇，真的没想到斑竹那么耐心地细致的解释得那么详细，再次万分感谢，斑竹辛苦了

hedonism555

不必客气。

[此贴子已经被作者于2005-1-26 22:42:23编辑过]