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The speed of sound is the distance travelled per unit time by a sound wave as it propagates through an elastic medium. In dry air at 0 ° C (32 ° F), the speed of sound is 331.2 metres per second (1,087 ft / s; 1,192 km / h; 741 mph; 644 kn). At 20 ° C (68 ° F), the speed of sound is 343 metres per second (1,125 ft / s; 1,235 km / h; 767 mph; 667 kn), or a kilometre in 2.91 s or a mile in 4.69 s.
Output:
what is the speed of the sound in air