I'll teach you how to do them, but not do them all for you.
2.
6:5 = ___:35
35 / 5 = 7
So you've got to multiply 6 by 7.
6:5 = 42:35
3.
2:3 = 20:___
20 / 2 = 10
So you've got to multiply 3 by 10
2:3=20:30
4.
36:24 = 6:___
36 / 6 = 6
So you've got to divide 24 by 6.
36:24 = 6:4
Keep trying and if you need more help feel free to ask.