Samacheer Kalvi 8th Science Unit 20 Book Back Answers: Samacheer Kalvi 8th Standard New Science Book Back 1 Mark and 2 Mark Question & Answers PDF uploaded and available below. Class 8 New Syllabus 2021 to 2022 Book Back Question & Answer available for both English and Tamil Mediums. Class 8th Science Book Unit 20 - Reaching the age of Adolescence Answers/Solutions are provided ...