Based on the CBSE syllabus, this book is meant for class 12 students of Bihar, Jharkhand and all other state boards following the CBSE syllabus. The lucid text is supported by clear, labelled diagrams. Extensive exercises, which follow each chapter, include all types of questions asked in the examination A large variety of objective questions with their answers is given in the last section of the book which will help students prepare for various competitive examinations.