GMAT PREP questions are quite similar to your exam day questions.So one should utilize this efficiently . GMATPREP gives you free 2 practice tests,which you can take around 5 times.Once you got exhausted with the tests use this document.This will really help you in boosting your score.
Answer for your question:
Googling is the best source to get explanation for those questions.Especially MANHATTANGMAT explanations are extraordinary for the GMATPREP questions.
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