This book is aimed at students of the 3rd grade of Vocational High School (EPAL). It contains: 

• Detailed theory. 
• Observations on the theory, which support the answers to the questions and the solutions to the exercises. 
• Methodology and Comments for solving exercises. 
• Solved exercises, as examples of solution methods. 
• Exercises for solving. 
• Review exercises at the end of each chapter. 
• Tests per teaching unit. 
• Topics that cover the entire range of knowledge that the student must have in order to fully meet the exam requirements. 

At the end of the book there are: 

• The solutions to the exercises in this book. 
• The topics and solutions of the topics in the Panhellenic exams.