If v and w are different integers, does v=0?
(1) vw = v^2
(2) w = 2
From Statement 1, we have:
vw = v^2
vw - v^2 = 0
v(w - v) = 0
and for this equation to be true, one of the factors on the left side must be equal to zero, so either v = 0, or v = w. Since we know that v does *not* equal w, the only remaining possibility is that v = 0, and Statement 1 is sufficient. Since Statement 2 is clearly insufficient, the answer is A.
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