Chapter 4, Lesson 1: Exercise 2AB Chapter 4, Lesson 1: Exercise 4A Chapter 4, Lesson 1: Exercise 4B Chapter 4, Lesson 1: Exercise 9AB Chapter 4, Lesson 1: Exercise 11A Chapter 4, Lesson 1: Exercise 14AB Chapter 4, Lesson 2: Exercise 2A Chapter 4, Lesson 2: Exercise 3AB Chapter 4, Lesson 2: Exercise 6AB Chapter 4, Lesson 2: Exercise 7AB Chapter 4, Lesson 2: Exercise 11AB Chapter 4, Lesson 2: Exercise 12B Chapter 4, Lesson 3: Exercise 1C Chapter 4, Lesson 3: Exercise 3A Chapter 4, Lesson 3: Exercise 4AB Chapter 4, Lesson 3: Exercise 7A Chapter 4, Lesson 3: Exercise 7B