XAMonline · Apr 14, 2016

Jeff was the backbone of Advanced Placement Biology sample test directions. He directed two other authors and evaluated the work product of others in this respect. Also, he did an SAT Biology book for us single-handedly. He was a great communicator.

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XAMonline · Sep 10, 2015

Jeffrey Sack is a professional academic writer with a specialty in Biology and the sciences in general. Communication skills were excellent because he really understood the assignment and was able to execute on it before his deadline but more importantly with the technical skill to write good sample test questions. Highly recommend this professional. We will invite to our Advanced Placement assignments next.

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