In this context, we are looking for a verb that would describe a miserable person's cry for help as it is cut off, which we notice by the dash at the end of the first quotation. Ran does not make sense, and laughed and exhalted are both the wrong tone. While stated is a perfectly reasonable answer grammatically speaking, it does not capture the moment as well as faltered, so that is the proper answer.

The sentence indicates an increase in intensity between being annoyed and the word that we need. Several of the options are relative synonyms for annoy ("vexed," "miffed"). The other options do not adequately express an intensification of anger. However, the word "enraged," though it may seem a bit strong, is indeed the best option.

The sentence is setting up a contrast of intensification. The cooling of temperatures is going from being "cold" to being colder. This is the key thing that you need to capture. The word "frigid", strictly speaking, means "very cold." None of the other options are appropriate for conveying intensification. The only other weather-related word, "balmy," means pleasantly warm. This definitely does not fit!  

This sentence contrasts how Gilbert acted in public and in private. Therefore, the best option for the sentence would be "privacy," for this describes his home as being the private space in which he was quiet—as opposed to the public space that is mentioned in the first part. The word "privacy" helps to establish the contrast quite clearly.

The old man was not just sitting on the porch, empty-headed and doing nothing. He was carefully watching things—observing them with care. He was not necessarily judging his neighbors (at least not yet). All we know is that the sentence is contrasting empty staring to the blank that we have to fill. "Observing" best fits for this—as the old man tries to figure out who stole the lawn decorations.

The key word in this sentence is "sufficient," which helps us understand the contrast being expressed. Although many might want to buy appliances with all the "bells and whistles," it is generally the case that they need one that "works well enough." The best adjective for describing this would be "basic." Words like "cheap" and "worthless" are too negative to match the clue "sufficient."

This sentence works by building from a legitimate amount to one that is extremely large and "over the top." The idea is that it is an almost incomprehensible expense to buy and own a hundred cars. Such an expense could be called "extravagant," meaning having no restraint or limits. The word is actually related to the word "vagrant," meaning a wandering person without work. Something "extra-vagrant" wanders around outside of the borders of being acceptable. It is "over the top."

The detective thinks that his option is the best available. This does not mean that it is the best and only option. It is not completely certain; it is just better than the others. Also, while it might be "interesting," we are not told that. Therefore, the best answer is "probable", which indicates that the option is likely, even if not certain.

The word "document" can be used as a verb to indicate the act of recording information. "Documentation" is the product of such recording. Clearly, the boss wants to have a clear record of any accidents. This means that he would like to see careful documentation of them. While "writing" might be tempting, the sentence is more specifically talking about the kind of writing involved in reporting. Thus, "documentation" is much better than "writing."

There are two facts in this sentence that will help you get the correct answer. The first is the fact that George is intelligent. Therefore, it is not the case that his low grades can be blamed on stupidity or something of that sort. The second hint is that he is said to show "laziness." This seems to indicate that he lacks a work ethic for his school work. This means that he likely is not very "motivated" to work. Therefore, of the options provided, this is the best. It is related to words for "motion." Motivation leads someone to do something—it moves him or her to do it.