I've found a lot of help on this forum for awhile but just registered. I'd like to retroactively say thanks for a lot of help the past few semesters. Im using the 4th edition of spivak calculus. I tried looking for what the solutions to *'ed problems but could not find anything. I have the answer book as well but was directed to another spot. For example in ch.1 : 21,22,23 have * next to them, the book itself does not have these and the solution guide says to see ch.5. Are these located throughout other chapters or just *'d to add emphasis?