<p>It looks like (1) is the textbook itself (is it custom publishing? for my LS2 course last quarter, it was a custom version with only the chapters of the book used in the course).</p>
<p>(2) looks like its just the e-book version of the text.</p>
<p>(3) looks like it’s the book plus some extra internet study guide.</p>
<p>If you have Phelan, you should buy a used copy of the most recent edition of Sadava and just buy a Prep-U account online. It’s the same thing but cheaper. You don’t even really read the textbook but it’s a good supplement, plus you might need it for LS1 depending on who your professor is.</p>