1.1 problem 2(a)
  1.2 problem 2(b)
  1.3 problem 2(c)
  1.4 problem 2(d)
  1.5 problem 2(e)
  1.6 problem 2(a)
  1.7 problem 3(a)
  1.8 problem 3(b)
  1.9 problem 3(c)
  1.10 problem 3(d)
  1.11 problem 3(e)
  1.12 problem 3(f)
  1.13 problem 3(g)
  1.14 problem 3(h)
  1.15 problem 3(i)