A car was driving towards a cliff at a constant speed. After a while, the driver stopped the car and honked the horn. After 4.8 seconds, an echo was heard. It is known that the propagation speed of sound in the air is 340 m/s, what is the distance from the car to the cliff when the echo is heard.
一辆汽车正朝山崖匀速行驶，一段时间后，司机让汽车停止前进并鸣笛，4.8秒后，听到回声．已知声音在空气中的传播速度是340米/秒，求听到回声时汽车距山崖的距离是多少．
<gadget id="calculator">4.8 / 2</gadget>
<output>2.4</output>

<gadget id="calculator">340 * 2.4</gadget>
<output>816</output>

<result>816</result>