Idk tbh looooooooooooooooooooool
The net force with be 10 N east. As both boys are pushing a wagon to the same direction, you just add the numbers together. If the directions were opposite like if it was the boy pushing 6 N east and the other boy pushing 4 N west...then it would come out as 2 N east (you subtract and go to the direction with the biggest number) if you have any confusions, feel free to ask
They are made of different substances
Separation by density filtration because lead slightly interacts with magnets also.
