the real problem is that "is" has no parallel in the first part of the comparison - i.e., the first part doesn't say "is emitted" or "are emitted" - and so the comparison is wrong.

twice more than 比...多两倍（三倍）
twice as much as 是...的两倍

If I use "with" to introduce a noun modifier I do not use a comma before it so that it is "touching" the noun it modifies; if I use "with" as an adverbial modifier I do use a comma before it.

in the construction "x of y, which", the referent could be either "x" or "y" depending on the surrounding context.

there's also a grammatical issue, too -- like/unlike must be followed by a noun or pronoun. a prepositional phrase is not a noun or pronoun.

老师，关于That能不能修饰人，我看ron在曼哈顿论坛回答过别人
RonPurewal
Re: Can "that" modify persons/people?
Tue Mar 10, 2015 2:48 am

in formal writing this is absolutely wrong; that function is served by "who(m)".

... and as long as we're on the topic, "which" can't stand for people either.

in informal usage you'll see these quite a bit, but informal writing isn't (and can't be) tested on this exam.

B选项their range extending from Alaska to Tierra del Fuego, from sea-level rain forests to the edges of Andean snowfields and ice fields at altitudes of 15,000 feet，不理解from sea-level前面为什么没有and呢？后一个from还是修饰extending吗？

C和D的语义上查了那么多，这题好难啊。。

B与原文中的方案无关。与什么可行性，有效性都无关。可行性是指这个方案能不能实施，如果说免费发放会让公司破产，那也ok。有效性是这个方案有没有用，如果说免费发放了还是不能提升广告收入，那么ok。B只是说“NN发行量下降的一个原因是报纸质量没有竞争对手好”，？？与方案无关的

The annual interest rate earned 不是 The annual interest

Ron给的例子感觉也可以解释，信被写的时间和数量超过没有关系。

my brother, who ate bagel bites for breakfast every single day of his high school career, graduated in 1994. --> correct; his eating bagel bites had no impact on his graduation date.
my brother ate bagel bites for breakfast every single day of his high school career, graduating in 1994. --> incorrect; these are two unrelated observations, but this construction erroneously implies some sort of relationship.

there's one simple way to eliminate (c), and that's to notice that "prefer ... compared to" is redundant.
you should just say "prefer ... to", as the word "prefer" already encodes the idea of making a comparison.

way to eliminate (b) is to realize that its construction - the placement of the commas and the word "that" - isn't right.
because of the placement of the commas and "that", this choice mistakenly puts "executives are convinced" in parallel with "1/3 of customers prefer...". that makes no sense.

'with' in choice b is also bad: it seems to imply that immigrants arrived with the law in their hands.
choice c implies that the immigrants themselves are 'a law passed in 19xx'

RON：Ironically, that's a strength on a test like the GMAT. Try to emulate it: If something seems complicated, step back and see whether you can make it simple.
Their goal is to create an exam that requires sharp thinking, but not specialized thinking.

没看懂grounding原来是停飞的意思

About 5 million acres是一个介词短语，怎么做主语啊？

可以理解为因果推理，反驳结论

不仅而且 怎么是not just 和 but also ？

https://www.manhattanprep.com/gmat/forums/as-the-honeybee-s-stinger-is-heavily-barbed-t7194.html