Sound travels through all mediums solid, liquid, and gas. Because sound is a vibration it will travel fastest through solids. This is because the vibrations that make up sound are carried from one place to another by neighboring molecules vibrating against one another. The density of the solid is higher than liquid and gas which means the molecules are more tightly packed and the vibration can pass from one to the next more quickly.
apple, earth. earth more massive than moon. astronauts showed this - armstrong etc
Answer:
Hans Lipperhey
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