Bats use their own ultrasonic waves to determine the distance to prey. A bat emits an ultrasonic wave and receives the reflected ultrasonic wave after 1.8 seconds. It is known that the propagation speed of the ultrasonic wave is 340 m/s. Please calculate the distance between the bat and the prey.
蝙蝠利用自己发出的超声波来确定与猎物的距离．一只蝙蝠发出超声波1.8秒后接到反射回来的超声波，已知超声波的传播速度是340米/秒，请算算蝙蝠与猎物之间的距离．
<gadget id="calculator">1.8 / 2</gadget>
<output>0.9</output>

<gadget id="calculator">340 * 0.9</gadget>
<output>306</output>

<result>306</result>