can't see how statement 2 is relevant. divisibiliity

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by Patrick_GMATFix » Sat Jul 17, 2010 1:37 pm
Hey gmatruler,

The question asks whether k is a power of 2, a number such as {2, 4, 8, 16...}

(1) if k = 2^6 then it will be a power of 2. However, k could be 2^6 * 13, which is not a power of 2. NOT SUFFICIENT.

(2) k has no odd factor (all factors break down to prime factors), so 2 must be the only prime factor of k (remember that k>1). SUFFICIENT

The answer is B. A more detailed solution as well as a step-by-step video solution is available at GMATPrep Question 1065. To practice similar questions, set topic='Number Properties' and difficulty='700+' in the Drill Engine.

-Patrick
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by aloneontheedge » Sat Jul 17, 2010 7:02 pm
Whats the OA,i feel it should be D.

If K is divisible by 2^6 then K= 2^6*n where n is any positive integer.

Stmnt B is suff: Since K is not divisible by any odd numbers it can be expressed in 2^r.
Plug any values (6,12 cannot be the values as they r divisible by an odd number)