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 3(a)
 1.7 problem 3(b)
 1.8 problem 3(c)
 1.9 problem 4(a)
 1.10 problem 4(b)
 1.11 problem 4(c)
 1.12 problem 5(a)
 1.13 problem 5(b)
 1.14 problem 5(c)
 1.15 problem 5(d)
 1.16 problem 8(a)
 1.17 problem 9
 1.18 problem 10(a)