Question

Fill in the blanks.
1. The frequency of a sound determines its_________.
2. Sound above 20000 Hz are called__________.they__________.
(can/cannot) be heard.
3. All unpleasant and undesirable sounds are known as_____________.
4. The SI unit of frequency of sound is__________.
5. The more is the frequency, shriller is the__________.
6. Sound cannot travel through_____________.
PLEASR HELP ME​

Answer 1

1-

2-ultrasonic ,cannot

3-noise

4-hetz

5--

6-vaccum