Which of the following describes the brightness of a star as we see it from earth?

Apebble is thrown into a calm lake, ripples are formed from the center and move outward. the water particles in the lake travel in a circular pattern that moves up and down on the surface of a lake, and the energy travels a) diagonally. b) downward. c) horizontally. d) upward.

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If you put a helium-filled balloon in the refrigerator, what will happen?