The Molitoris book is a horrendously inaccurate representation of the GRE Physics Test. The problems are uncharacteristically difficult and many calculations are too difficult to do with a paper and pencil in 1 minutes time.
You prep time is better spent reviewing the actual released Physics GRE questions from ETS. These are actual GRE questions
from previous years. Also, I have heard there are usually several questions from the practice tests which are reused every year.
The four released tests can be found here, among other websites:http://www.physics.ohio-state.edu/undergrad/ugs_gre.php
Solutions to all released problems:http://grephysics.net/
These questions should be the focus of your prep efforts, in my opinion. Don't bother with the Molitoris book. It isn't a good representative and is full of errors. Although, its review of physics is somewhat useful, the fake exams aren't.