Mrs. Ruiz made a mountain model out of plastic foam and Ms. Ana made a similar model out of clay. They each poured the same amount of water on their mountain. Then they measured the amount of runoff collected at the bottom. Which is the tested variable?

Consider hydrogen in an excited state n = 5n=5 that emits photons to reach the ground state. there are various possible transitions other than straight to the ground state that can occur; for example, it can drop to the n = 3n=3 state followed by the n = 3n=3 to the ground state transition. which of the possible transitions will result in the emission of a photon in the visible region?