Hey everyone. I'm studying for the Open Exam this summer and this is going to be my first year participating in the competition. I have a Campbell Biology Eleventh Edition Textbook that I am using to study, but I read online that the Eleventh Edition is not as good as the Ninth or Tenth Editions. Is this true? Also, is there anything else that I can study to prepare for the Open and Semifinal Exams? Thanks.