The correct answer is: [A}: " 6 units " .
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Step-by-step explanation:
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From the diagram attached, we are given that "AB" = 12 . It seems reasonable that "AR" is "one-half" the length of: "AB" .
(1/2) * (12 units) = 6 units.
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Furthermore, let us consider the other TWO (2) answer choices given:
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Choice: [B]: " 12 units" ; is INCORRECT; since we are given that "AB" = 12 units; and "AR" appears to be "(1/2)" the length of "AB" ; or MUCH less than the ACTUAL length of "AB" — at any rate (refer to diagram provided.
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Choice: [C]: " 24 units " ; is INCORRECT; since we are given that "AB" = 12 units. As aforementioned, "AR" appears to be "(1/2)" the length of "AB" ; that is, " 6 units " ; and: " 24 units" is TWICE the length of "AB" —
{Note that "12 units" * 2 = " 24 units " .}.
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As such: The best answer—and correct answer—is:
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→ Answer choice: [A]: " 6 units " .
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