Many teachers do not require the key as they do the answer part for themselves and I do not indicate in the descrption that the key is included. If you would have emailed me, I would have gladly provided you with the answer key as I have done in the past for teachers. In many cases I do not put keys here as I have had students purchase the items and got the key as well.
If you send me your email address, I can send you the answers for Chapter 1-4. I think you must have bought the questions for Ch. 5 & 6 from another seller as I do not have those questions listed.