Answer:
d)
Explanation:
Electrons are lost or gained when the ballon is rubbed with a PVC. As the rubber ballon lost electrons, it will have more protons, hence the positive charge. (More protons than electrons in the ballon).
Answer:
Reflective clothing. So vehicles can see them and stuff.
The height of the tennis ball,relative to the ground is H=h max+h-->h max-the maximum height that the tennis ball reaches relative to the roof of the building; h-the height of the building;h max =v0^2/2g=24,2m(g=10m/s^2).H=gt^2/2=>24,2+h=gt^2/2=>h=gt^2/2-24,2=180,6m