Recommended exercises:

Chapter 4:  2, 3, 4, 8, 9, 11, 15

Chapter 5:   1, 3, 5, 7, 8, 12, 15

Chapter 6:  1, 4, 6, 7, 9, 13

Chapter 7:  1, 3, 6, 7, 11, 16

Chapter 8:  1, 3, 8, 10, 14

Chapter 9:  2, 3, 6, 8, 10

Chapter 12:  1, 4, 5, 6, 7, 10 (solutions)

Chapter 13:  1, 2, 3, 6(solution), 9, 11 (solutions)

Chapter 14:  3, 4, 5, 6,7, 8 (solutions)

Chapter 15:  1, 3, 4, 8, 9, 10 (solutions)

Chapter 16:  1, 2, 3a, 3c, 5, 6 (solutions)

Chapter 17:  3, 5, 6, 9, 12

Chapter 18:  1, 2, 4, 6, 7, 11, 13, 15 (solutions)

Chapter 19:  3, 4, 6, 7, 8, 10, 13 (solutions)

Chapter 20:  2, 4, 8 (solutions)