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gkammaje
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OA C
thanks
thanks
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My anwser is (C).
From (1), we know that 10^d is a factor of 30!, and 30!=30*...*25*...*20*...*15*...10*...*5*...1 = 10^7 * a, where a is an integer.
So from (1), d can be any interger from 1 to 7, thus insufficient.
From (2), we know that d>6, alone is insufficient.
Combine (1) and (2), d must be 7, so the both together are sufficient.
Answer is (C)
