1. What unit is used to represent frequency?
A. Decibels
B. Hertz
C. Newtons
D. Ultrasound
2. When can we say that the sound is harmonious? The sound produced ___.
A. Is pleasing to ears
B. Reaches to 6000 decibels
C. Can be heard by everybody
D. Causes other objects to vibrate
3.What is the unit used in measuring sound?
A. Decibels
B. Kilometers
C. Liters
D. Yard
4.Which of the following materials where sound can travel?
A. Metals
B. Water
C. Wood
D. All of the above
[tex]help \: me \: please[/tex]
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