I will try to figure some of these out.
1. O is not given, neither is the center of the dilation.
2. A dilation divides all factors involved, including segment length, by its scale factor. So the answer is 20/-6, which you can simplify. A hint, though, whether a dilation is positive or negative only determines which side of the center of the dilation the result is on.
3a. 7 ways, since we can decide which point goes in any certain spot.
3b. 14 ways, since we can now reflect.
4. We can see that if A is 40 units away from B than it is 20 units away from the line. Given that since C goes to C it is on the line, how close can A be to C?
5. Most of the information does not matter since it does not change shape, only location. Use the dilation information I gave in problem two (just with scale factor -2 instead) to figure it out.
6. I don't know how to do this one.
7. If triangle ABC is equilateral, then the scale factor is -2. Otherwise, I don't think any dilation can do this.