1.1 problem 1(a)
 1.2 problem 1(b)
 1.3 problem 1(c)
 1.4 problem 1(d)
 1.5 problem 1(e)
 1.6 problem 1(f)
 1.7 problem 2(a)
 1.8 problem 2(b)
 1.9 problem 2(c)
 1.10 problem 2(d)
 1.11 problem 2(e)
 1.12 problem 3(a)
 1.13 problem 3(b)
 1.14 problem 3(c)
 1.15 problem 3(a)
 1.16 problem 4(a)
 1.17 problem 4(b)
 1.18 problem 4(c)
 1.19 problem 4(d)
 1.20 problem 5(a)
 1.21 problem 5(b)
 1.22 problem 5(c)
 1.23 problem 5(d)