C. Give one word answers. 1. The occasional spark in the clouds. 3. 2. The sound from lightning in the clouds. The kind of charge acquired by glass rod on rubbing with a piece of silk. 4. The kind of charge developed in a plastic comb on rubbing through dry hair. 5. Kind of charge on two bodies if they repel each other. 6. Hardened and glass like resin. 7. Hardened dark wood with gum like deposits in its cells. 8. The apparatus to test the presence of static electric charge in a body. 9. The point inside mantle where the sliding rocks rub against each other. 10. The point on the surface of the earth vertically above the 'focus' and considered as the point of origin of the earthquake.​