88.6 Chapter 2. Differential equations of first order. Exercise at page 38

88.6.1 problem 1
88.6.2 problem 2
88.6.3 problem 3
88.6.4 problem 4
88.6.5 problem 5
88.6.6 problem 6
88.6.7 problem 7
88.6.8 problem 8
88.6.9 problem 9
88.6.10 problem 10
88.6.11 problem 11
88.6.12 problem 12
88.6.13 problem 14