Elements of Latin is a fantastic textbook, written after Dr D'Ooge's more famous Latin for Beginners, breaking down the topic into smaller lessons and more of them. This answer key not only contains the answers for all the exercises but also translations for the play and the original stories in the appendices of the textbook. You can find this answer key online at archive.org or get this printed copy to go with the coil bound textbook that should also be available here at lulu.com.