2.1 problem 1
2.2 problem 2
2.3 problem 3
2.4 problem 4
2.5 problem 5
2.6 problem 6
2.7 problem 7
2.8 problem 8
2.9 problem 9
2.10 problem 10
2.11 problem 15 b(1)
2.12 problem 15 b(2)
2.13 problem 15 b(3)
2.14 problem 15 b(4)
2.15 problem 15 b(5)
2.16 problem 16 (i)
2.17 problem 16 (ii)
2.18 problem 16 (iii)
2.19 problem 16 (iv)
2.20 problem 16 (v)
2.21 problem 16 (vi)
2.22 problem 16 (vii)
2.23 problem 16 (viii)
2.24 problem 19 a(i)
2.25 problem 19 a(ii)
2.26 problem 19 a(iii)
2.27 problem 20
2.28 problem 21
2.29 problem 22