20.1 Chapter 2, section 7, page 37

20.1.1 problem 1.a
20.1.2 problem 1.b
20.1.3 problem 1.c
20.1.4 problem 1.d
20.1.5 problem 1.
20.1.6 problem 3.a
20.1.7 problem 3.b
20.1.8 problem 5.a
20.1.9 problem 5.b