The speed of sound in air is 340 meters per second, how many kilometers per minute?
声音在空气中的传播速度为每秒340米，合每分钟多少千米？
<gadget id="calculator">1 / 60</gadget>
<output>1/60 = around 0.016667</output>

<gadget id="calculator">0.34 / (1/60)</gadget>
<output>20.4</output>

<result>20.4</result>