10. waves bounce back when they meet a surface. this is

Which step in naming unsaturated hydrocarbons is used for alkenes but not alkynes

Consider the story you just read. all but one of the choices below indicate that something is living.

Alidded glass container is filled with a colored gas. after a period of time, it is observed that the gas is uniformly spread throughout the box and that the movement has slowed considerably. next, a warm iron plate is carefully placed under the box. why is there resumed movement of the gas in the container?