You are given a geometric mathematical question. Questions in this task often involve shapes and Geometric Relationships. You are also given 4 or 5 answer options (associated with "A", "B", "C", "D", "E"). Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D', 'E'. LaTeX mathematical format (the standard way to express mathematical expressions in the typesetting software known as LaTeX) is used to express equations. Each question is solvable with high school math knowledge.

Q: \begin{gather} x^2 + y^2 + 4x - 2y = -1 \end{gather} The equation of a circle in the xy-plane is shown above. What is the radius of the circle?
(A)2 (B)3 (C)4 (D)9

A: A
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Q: A rectangular solid that has a width of 8, a length of 8, and a height of 12 is divided into 12 cubes, each of equal volume. What is the length of the edge of one of these cubes?
(A)4 (B)6 (C)8 (D)12 (E)64

A: A
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Q: If m is an integer and m, m + 1, and m + 2 are the lengths of the sides of a triangle, which of the following could be the value of m? I. 1 II. 10 III. 100
(A)I only (B)II only (C)III only (D)II and III only (E)I, II, and III

A:
D
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