X/336 = 6/(462 - 336)

n*n - k*k = 48
(n - k) * (n + k) = 48
n = 7, k = 1
n = 13, k = 11
n = 8, k = 4

1200-800+400=550+X

1+9
2+8
3+7
4+6
0
5
要取7个才能确保有两张纸的数字和为10，因为6个的极端情况（012345或056789）

！！简单题，错误！

考察
前：between 必须加and，而不是to，from to也可以，排除c
后：与未画线部分联系，应该是as much as。去掉ade；；再有，未画线前面部分有个their feeding，也可以推测出画线部分应该是复数主语，即sperm whales，不要看到“a ton of squid a day”就以为是a sperm whale。一定要结合前后文未画线部分

针对此类问题，抓住一个核心，无论Rita先拿走几根木棍，Sam总能够使第一个来回两人拿走的木棍总数为6，举个栗子，如果Rita先拿走1个，Sam就拿走5个，如果Rita拿走5个，Sam就拿走1个。所以，选项中是6的倍数的是正确选项，无论Rita怎么拿，Sam都会赢

B错选 packaging material占household garbage很小的一部分，但是有可能其他的household garbage燃烧时都不会出现dioxin啊

考察：
前：Scientists believe that X--- that Y. X and Y are parallel clauses. ---- OG 破折号后可以加that也可以不加
中后：reduce their number优于被动语态
关键：！！！与未画线部分联系！！！最后and平行，and thus+n，那前面也是n，排除cde，而a中reducing 的逻辑主语变成了 ancestors，错误

考察：
句意
前：advocating为reformers的后置定语，现在分词形式表主动，ing定语表主动。advocate提倡，拥护
后：拥护的是一种方法，to reform prisoners， as the means to
e中advocate用了倒装但是引起了句意混淆，advocate的东西应该紧随其后，与c对比，排除

But while nutritionists usually advise people to avoid high-sugar and high-glycemic-index foods, despite any nutritional benefits they may confer

考察：
未画线部分and giving的平行

. Aspens' need for fire may seem illogical since aspens are particularly vulnerable to fires; whereas the bark of most trees consists of dead cells,

The maternal strategy evolved by harbor seals may have to do with their small size and the large proportion of their fat stores depleted in lactation.

Zoologists had assumed that females of all phocid species, by contrast, use a fasting strategy in which mother phocids, having accumulated large energy stores before they arrive at breeding sites, fast throughout the entire lactation period, which lasts from 4 to 50 days depending on the species.

Until recently, zoologists believed that all species of phocids (true seals), a pinniped family, use a different maternalstrategy than do otariids (fur seals and sea lions), another pinniped family.

ultimate goal 跟 B 冲突 不是ultimately reduce
guests that D 错 guests 只能who
reduce the number of 不是 reduce the guests A 错
C reduce expressions 在逻辑上错误

他因：11400年前有通道 可以通过

speeds that will be much higher than are currently possible
that→指代单数名词；

experiments剩下了BE

shift和change一个意思，这就重复了，所以DE不对。