Exercise 5.1
Exercise 5.2
Exercise 5.3
Exercise 5.4
Exercise 5.5
Exercise 5.6 - version of Progam 5.2
Exercise 5.6 - version of Progam 5.3
Exercise 5.6 - version of Progam 5.4
Exercise 5.6 - version of Progam 5.5
Exercise 5.7
Exercise 5.8