1) What is vibration? a) how loud a sound is b) the loudness or softness of a sound c) the quick back and forth movement of matter 2) An ________ is a reflected sound. a) Vibration b) Echo c) Pitch d) Volume 3) Sound waves travel the FASTEST through _____________. a) gases b) space c) solids d) liquids 4) The hearing range of human ear is a) 20 Hz to 20,000 Hz b) Less than 20 Hz c) 20 Hz to 25,000 Hz 5) ____________ is the highness or lowness of a sound. a) Amplitude b) Volume c) Pitch d) Vibration 6) What is frequency? a) the number of vibrations per second b) how high or low a sound is c) the back and forth movement of matter d) the loudness or softness of a sound

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