When this element was discovered, it exhibited luster and malleability, and it reacted very vigorously with water. To which group does this element belong?

What can be added to the examples section of each circle? endothermic: ice melting into water, and a heat pack becoming warm exothermic: a glow stick glowing, and fireworks exploding endothermic: ice melting into water, and an instant ice pack turning cold exothermic: fireworks exploding, and gasoline burning endothermic: a glow stick glowing, and a heat pack becoming warm exothermic: an instant ice pack turning cold, and ice melting into water endothermic: gasoline burning, and an instant ice pack turning cold exothermic: ice melting into water, and an instant ice pack turning cold

Can someone me with questions 15 to 17 plz.

George is a dalmatian puppy. describe what happens to light that allows you to see george’s black and white coat.