B. Harmonica C. Dholakd. Piano1. A sound is produced because of(vibrations/molecules).(Music/Sound) is our basic means of communication.3. Sound needs a— (source/medium) to travel in.4. The unit of frequency is(hertz/seconds)5. Time period is measured in(hertz/seconds).2.B. Fill in the blanks with the correct words.

B. Harmonica C. Dholakd. Piano1. A sound is produced because of(vibr

1.	B. Harmonica C. Dholakd. Piano1. A sound is produced because of(vibrations/molecules).(Music/Sound) is our basic means of communication.3. Sound needs a— (source/medium) to travel in.4. The unit of frequency is(hertz/seconds)5. Time period is measured in(hertz/seconds).2.B. Fill in the blanks with the correct words.
Answer» ONG>ANSWER: i DONOT KNOW the answer