80.1 Chapter 1. section 5. Problems at page 19

80.1.1 problem 2
80.1.2 problem 3
80.1.3 problem 4
80.1.4 problem 5
80.1.5 problem 6
80.1.6 problem 16 (a)
80.1.7 problem 16 (b)
80.1.8 problem 17 (a)
80.1.9 problem 18