{:(,"Column A",,, "Column B"),(A., anglei = angler, (), a., 0.1 s),(B., "Persistence of hearing", ( ), b., "Infrasonic"),(C., "Dolphins", ( ), c., "Law of reflection of sound"),(D., "Carpets", ( ), d., "Echoes"),(E., 10 Hz, (), e., "Reduce noise pollution"):}

{:(,"Column A",,, "Column B"),(A., anglei = angler, (), a., 0.1 s),(B.

1.	{:(,"Column A",,, "Column B"),(A., anglei = angler, (), a., 0.1 s),(B., "Persistence of hearing", ( ), b., "Infrasonic"),(C., "Dolphins", ( ), c., "Law of reflection of sound"),(D., "Carpets", ( ), d., "Echoes"),(E., 10 Hz, (), e., "Reduce noise pollution"):}
Answer» Solution :A - c `" "` When a sound wave is reflected, the angle of incident sound (i) is equal to the angle of reflected sound. B - a `" "` The persistence of hearing HUMANS is 0.1 s. C - d `" "` Dolphins use echo method to CATCH their PREY. D - e `" "` Carpets are sound ABSORBING materials and reduce noise pollution. E - b `" "` Sound with frequencyless than 20 Hz is knownas infrasonic.