0 points: Chapter 0, section 1: Exercise 6

2 points: Chapter 0, section 1: Exercise 7

0 points: Chapter 0, section 1: Exercise 10

2 points: Chapter 0, section 1: Exercise 11

0 points: Chapter 0, section 1: Exercise 14

2 points: Chapter 0, section 1: Exercise 15

2 points: Chapter 0, section 1: Exercise 16. You do not need a formal proof for this, but you do need to supply some reasoning.