BIO-111 and MAT-143 book costs are included as a fee with your tuition. Spring 2018 is the first semester this is being applied, so any previous books for these courses will not save you money.
Some courses require codes that are usually bundled with the book when you buy it at the bookstore. Some codes can be purchased separately and contain access to an E-book. Some courses may be using a different edition of the book.
Please check the bookstore website or contact the instructor of the course so you do not have to buy books twice.