For those, like myself, who need practice on Gauss’s Law problems there are several resources available that I have found useful.
Two are found on YouTube. The Organic Chemistry Tutor and Michel Biezen’s ilectureonline.com. Both have good videos on Gauss’s Law problems. Professor Biezen’s series of problems are especially good and are solved step by step in great detail.
Another good resource is “Essential Calculus-based Physics Study Guide Workbook” By Chris McMullen. This is volume two of a series of physics workbooks. Volume two covers electricity and magnetism. After working through the Gauss’s Law problems I was well prepared for professor Shankar"s problem set.