Exercises 7.1

7, 11, 15*, 19, 21*, 28*, 29, 33*, 39, 41*, 51

Exercises 7.2

5*, 7, 9, 11, 13*, 17, 19, 45

Exercises 7.4

11, 13*, 23*, 29, 33, 43, 45, 51, 57

Exercises 7.8

7, 11*, 13*, 19, 29, 33, 37*, 49, 51, 59