Explain the expression “light travels at a speed”.

The process of a material going through a change of state from a gas to a liquid

By examining a wave’s pattern after it interacts with a barrier or gap, measurements can be made to better understand certain wave phenomena. what is a broad question you can answer by doing this experiment?

Mary starts from her house, walks 80 meters south, and stops to chat with her aunt on the sidewalk. after chatting for a few minutes, she walks 125 meters to the west to meet a friend and then walks 45 meters north with her friend to a cafe for lunch. overall, she takes 10 minutes to do all this. what is mary’s average speed?