Does anyone know questions 3, 5, and 6 on the first picture? also number 7 on the last picture

On first picture:

3) 1,000 Newtons on each arrow.

5) They have the same force on both sides, so either one could win.

6) The amount of force on one side would have to increase or decrease.

Last picture:

7) It's moving to the right because they are tugging it, and the other person is just holding it.

You should try to read a little more, I'm only in elementary school.

Yes you are correct use the scientific method