exercise 1, exercise 2, exercise 3, exercise 4
exercise 1, exercise 2, exercise 3
exercise 1, exercise 2, exercise 3, exercise 4, exercise 5, exercise 6, exercise 7, exercise 8, exercise 9, exercise 10, exercise 11
exercise 1, exercise 2, exercise 3, exercise 4, exercise 5, exercise 6, exercise 7, exercise 8, exercise 9, exercise 10
exercise 1, exercise 2, exercise 3, exercise 4, exercise 5
test 1 (type I), test 2 (type I and II)