The sentence contrasts the "politicians' desire to speed up" with the correct answer choice. therefore, the correct word will mean extremely slow, which is the definition of glacial.

The key to finding this answer is the phrase "a basis in nothing."  The correct answer will demonstrate the subject's lack of reasons for his hatred. "Irrational," meaning unreasonable or without logic, is the best choice.

The sentence contrasts the river at high tide and low tide, and says the river was "a convenient passageway . . . at high tide." The correct answer, modified by "barely," will mean passable or suitable to get through, the definition of "navigable."

The word "constantly" is the best clue in the sentence to find the answer.  The correct word will indicate the ever present nature of his "surly demeanor." "Congenital," meaning present since birth, is the correct answer.

The evangelist is actively trying to avoid scandals, so he needs to live his life in a way that does that. The correct answer will indicate he is trying to live perfectly or without criticism, which is the definition of "irreproachably."

The fact the prosecutor is charged with a cover up and that the evidence would exonerate defendants indicates the seriousness of the evidence. The correct answer will demonstrate that seriousness. "Pertinent," meaning relevant, is the best fit in the sentence.

The "identity theft" changed the woman's attacks outlook on using her credit card, and the correct answer will reflect her reaction to the identity theft. "Wary," meaning hesitant or cautious, is the best fit among the answer choices.

Being thrown out of a game is a very serious penalty, and the correct answer will indicate the seriousness of the foul to warrant such a punishment. "Egregious," meaning extremely or obviously bad, is the correct answer.

The key phrase is the subordinate clause, "who was quite aware of his quick temper." The volatile situations are compared to this temper, which alters quickly. The most tempting wrong answers are "agitated" and "unknown." Either of these (particularly the latter) could indicate a changing mood that is volatile; however, "mercurial" is more directly related in meaning to such a characteristic of having a changing mood.

The second sentence gives the sense of the blank. The grandmother clearly does not want the medicine; therefore, she must not know about it. Although we might be tempted by "underhandedly," there is not reason to add such negative tones. "Silently" might be tempting because of the secrecy, but it is not the best option. The best answer would be "surreptitiously," which best captures the secrecy of the grandson's action, without adding any other meanings.