Question

a unit called decibel
12. The sound cannot travel in solid materials.
13. Angle of incidence is greater than angle of ction​

Answer 1

Answer:

decibel (dB) unit for expressing the ratio between two physical quantities, usually amounts of acoustic or electric power, or for measuring the relative loudness of sounds. one decibel (0.1bel) equal 10 times common logarithm of the power ratio.