This math B+C problem set and answer key are perfect for studying. - Title: Focus Gold Math B+C - Edition: 5th Edition - Contents: Problem set and answer key There are some notes written in the problem set, as shown in the photos. The answer key seems to be free of writing, but please forgive any oversight. Due to the writing and signs of use, the price has been reduced. Please refrain from complaints after purchase. Thank you for looking.