1) It is a form of energy.It is made when something vibrates a) sound b) loud sound c) soft sound 2) These are the things that move back and forth really fast. a) sound b) vibration c) energy 3) It is pleasant to the ear a) loud b) vibration c) soft 4) It is unpleasant to the ear and be easily heard a) loud b) soft c) vibration 5) Some sounds are too loud that it can hurt our ears. a) True b) False c) Maybe

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