34. The speed of sound in a stationary air is 340 m/s. A police car with its 300-Hz siren turned on is moving toward a wall at 180 km/hour. The frequency of the reflected wave that the driver of the car hear is:
(A) 403 Hz
(B) 223 Hz
(C) 344 Hz
(D) 351 Hz
(E) none of the above.
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統計: 尚無統計資料
統計: 尚無統計資料