18.1 problem section 9.2, problem 1
  18.2 problem section 9.2, problem 2
  18.3 problem section 9.2, problem 3
  18.4 problem section 9.2, problem 4
  18.5 problem section 9.2, problem 5
  18.6 problem section 9.2, problem 6
  18.7 problem section 9.2, problem 7
  18.8 problem section 9.2, problem 8
  18.9 problem section 9.2, problem 9
  18.10 problem section 9.2, problem 10
  18.11 problem section 9.2, problem 11
  18.12 problem section 9.2, problem 12
  18.13 problem section 9.2, problem 13
  18.14 problem section 9.2, problem 14
  18.15 problem section 9.2, problem 15
  18.16 problem section 9.2, problem 16
  18.17 problem section 9.2, problem 17
  18.18 problem section 9.2, problem 18
  18.19 problem section 9.2, problem 19
  18.20 problem section 9.2, problem 20
  18.21 problem section 9.2, problem 21
  18.22 problem section 9.2, problem 22
  18.23 problem section 9.2, problem 23
  18.24 problem section 9.2, problem 24
  18.25 problem section 9.2, problem 25
  18.26 problem section 9.2, problem 26
  18.27 problem section 9.2, problem 27
  18.28 problem section 9.2, problem 43(a)
  18.29 problem section 9.2, problem 43(b)
  18.30 problem section 9.2, problem 43(c)
  18.31 problem section 9.2, problem 43(d)
  18.32 problem section 9.2, problem 43(e)
  18.33 problem section 9.2, problem 43(g)