Compared to regulations in other countries, those of the United States

First things first - let's start reading the questions before we even read the text. Some questions it will be possible to answer by reading just one small portion.
Let's do it:

Question 1

It can be inferred that, compared to the United States, Japan spent less on:

This question should send us looking for a place in the text in which both the US and Japan are mentioned. We'll find it in the third paragraph:
For example, one study of a multinational firm with operations in the United States and Japan found that pollution levels in both countries were similar, despite generally higher pollution abatement expenditures in the United States
OK, so we know that the US spend more on "pollution abatement expenditures" - but what does that actually mean? Since the question tells us to infer, we're going to have to look for more clues. Let's read the next sentence:
The higher costs observed in the United States thus were due in large part, not to more stringent standards, but to the higher regulatory transaction costs.
There we have it: the US had higher regulatory transaction costs. Looking at the answer choices, it is clear this refers to (C) regulating firms.

Question 2

The author of the passage would disagree with which of the following?

This question sends requires us to actually read the entire passage, since it doesn't refer to any specific part.
After doing so, we'll review the answers, and ask ourselves - which of these does not fit?

A Some nations are likely to put more focus on regulating industry than allowing industry a measure of autonomy. Sure, the US for example. Not our answer!
B Varying levels of regulation can lead to similar levels of pollution. yes: the entire passage describes the different regulatory attitudes of different countries, while the final sentence explicitly says they end up with similar pollution levels. Not our answer!
C There is a complete lack of transparency in the different standards used by countries. Nowhere is this stated, and the final sentence says the opposite: different countries share information. Looks like our answer! We'll keep looking though, in order to be sure.
D The United States tends to regulate only a few aspects of the overall production process. Yup, this is said explicitly in the third sentence - some aspects are regulated, others ignored. Not our answer!
E Analogies can aptly summarize the primary differences between the environmental practices of two countries. We know of at least one case in which the author thinks this is true: the hare and tortoise analogy described in the third paragraph. Not our answer!

Questions 3

The author implies that a country described as a "tortoise" is more likely to favor:

This question sends us looking at the place where "tortoise" is mentioned, the third paragraph:
Sweden (the tortoise) used a more collaborative process that stressed results but worked with industry in deciding how to achieve them
Since it asks us what is implied, we must think logically about what this means, and not expect to find an answer which is stated precisely. If the process is collaborative and works with industry, it follows that Sweden would favor some measure which brings the industry into the process of building policy. This is exactly what (C) tells us: a process of decision-making that includes industry.

Question 4

Based on information in the passage, it can be inferred that the author believes that countries similar to the United States in terms of environmental policy

Since this questions is quite open-ended, let's review the answers:
A have poorer air quality than countries in which industry plays a role in environmental decision making We're explicitly told countries with different approaches can have similar levels of pollution. No!
B will spend more on regulation instead of allowing firms to influence environmental policy This looks right - we are told that the US has higher regulatory costs than other countries, and that is less likely to allow firms to influence policy. We'd expect countries similar to the US to be the same.
C do not stress immediate results but prefer an approach that will yield long term success This is not stated: stressing immediate results appears to be true for both approaches, while focusing on the long term is not described or implied.
D are likely to have less pollution abatement expenditures than most other countries The opposite is true
E focus more on collaborative processes and less on sanctions Once again, the opposite is true

Question 5

According to the passage, as a result of stringent regulation of specific aspects of the production process other aspects of the production process are

Well, since this question is about "according to the passage", we'll take the Precise approach and find the specific place in the passage referred to:
Regulation in the United States tends to isolate specific aspects of production processes and attempts to control them stringently, which means that some aspects of business are regulated tightly, although sometimes not cost-effectively, while others are ignored.
There we have it - other aspects are ignored. Looking at the answers, this is clearly (E) virtually overlooked

Question 6

The primary purpose of the passage is to

This is a question which requires us to have read the the entire passage, and once we have done that, to think about what we think it's goal is. Well, the first paragraph is a comparison of the US's environmental policy practices with other countries', the second is a continuation of this comparison, and the third is an illustration of the comparison. So, it's clear the goal is to describe the way environmental policy is carried out in the US and compare it with other countries. Looking at the answers, it is clear this is (D) discuss the scope of environmental regulation in the United States and how it compares to that of other countries .

Another approach to solving this question would be to review the answers, and ask ourselves for each: if this were the primary concern, what type of passage would we expect to see? Is ths similar to the existing passage?

A contrast the environmental practices of the United States across a period of time This would be a description of changes in the US policy over time. No!

B advocate for an overhaul in the way in which environmental regulation is carried out in the United States This would mean that it should be clear which side of the comparison is preferable. But the bottom line here is that similar pollution levels are achieved across the different countries. No!

C compare the environmental and industry practices of two countries This should be a detailed comparison of two countries only - but the US is compared to LOTS of countries - nope!

D discuss the scope of environmental regulation in the United States and how it compares to that of other countries We'd expect a passage with this concern to describe in detail how environmental regulation is carried out in the US, and then describe how other countries are different. Yup, that's exactly what we have!

E describe prevalent theories in environmental policy and which one is best for the United States a passage with this description would be quite theoretical, and would also have a clear assertion as to which theory is best for the US. this is not what we have at all