The wheel diameter of a battery car is 0.5m. If the wheel of this battery car rotates 300 times per minute, how many meters can this battery car travel per minute?
一辆电瓶车车轮直径是0.5m，如果这辆电瓶车车轮每分钟转300圈，那么这辆电瓶车每分钟可行多少米？
<gadget id="calculator">3.14 * 0.5 * 300</gadget>
<output>471</output>

<result>471</result>