The adjective "precise" refers to an extremely accurate or specific measurement or assessment. "Exact," which also refers to an accurate or correct quantity, is our answer. "Careless" is clearly incorrect, since it describes something that is sloppy and unlikely to be perfectly measured. You might use the word "immature" to describe a person who acts unusually young and inexperienced; neither this term nor "incomplete" (unfinished) is related to the given word.

When someone is "ravenous," they are very hungry, often in a ferocious way. If you've ever said you were "starving," or eaten your dinner in a matter of minutes, you've probably felt ravenous before. When a person is "content," he or she is happy with his current situation, which would not be the case if he were uncomfortably hungry. An "overwhelmed" person feels like he or she has been overcome by responsibility or feelings, and "colorful" simply means containing many colors or is used to refer to an interesting person.

To have a "hectic" schedule is to have an extremely busy one, so "busy" is the correct answer. As for the other answer choices, none are close in meaning to "hectic": "solitary" means alone; "radiant" means glowing; "surprised" means astounded or shocked; and "determined" means firmly decided on something.

If somewhere is “arid” that means it is very dry and does not get very much rain. So the desert is very “arid.”

“Rash,” when used to describe an action, means hasty, rushed. To provide further help, “sluggish” means tired, lacking energy; “vibrant” means bright and colorful.

The adjective "intricate" refers to something that is complex or nuanced. It is sometimes used to describe physical complexity (like an intricate system of highways), but also applies to ideas that may be difficult to grasp. "Complicated" is the clear synonym here. Of the remaining choices, both "straightforward" and "simple" are antonyms of the given word, since they convey a lack of complexity. "Unified" is used to describe groups that have been united or brought together.

The word "equivalent" has a base that is certainly quite familiar to you: "equ-" as used in "equal," "equally," and so forth. When two things are "equivalent," they are the same, like 2 and 1 + 1. Equivalence indicates a greater degree of correspondence than mere similarity. Two people might be similar in appearance, but equivalence is strict equality. Therefore, the best option among those given is "identical," which indicates such strict equivalence.

"Destructive" means causing damage. Ruinous also means disastrous or causing damage, so "ruinous" is the correct answer. As for the other answer choices, "considerable" means noticeable due to large size or amount, "brief" means short or quick, a "frontier" is a border between two countries, and to "boast" means to talk about yourself and your achievements with pride.

The correct answer is "drowsy," which means groggy or sleepy. "Lively," "energetic," and "active" are all opposites of "tired." "Drowsy" is the only word that means nearly the same thing as "tired."

"Auspicious" is an adjective that can mean either "conducive to success; favorable," or "giving or being a sign of future success." So, we need to pick out an answer choice that is an adjective and means something like "favorable." So, "ominous" cannot be the correct answer because "ominous" means "giving the impression that something bad or unpleasant is going to happen; threatening; inauspicious," so "ominous" is an antonym of "auspicious." "Promising," however, is an adjective that means "showing signs of future success," and because it is the answer choice closest in meaning to "auspicious," "promising" is the correct answer.