The scale of a picture is 1:5000. The radius of a circular pool measured on this picture is 0.5 cm. What is the area of the pool in square meters?
一幅图的比例尺是1：5000，在这幅图上量得一圆形水池的半径是0.5厘米，这个水池的占地面积是多少平方米．
<gadget id="calculator">1 / 5_000</gadget>
<output>1/5_000 = around 0.0002</output>

<gadget id="calculator">0.5 / (1/5_000) / 100</gadget>
<output>25</output>

<gadget id="calculator">25 ** 2</gadget>
<output>625</output>

<gadget id="calculator">3.14 * 625</gadget>
<output>1_962.5</output>

<result>1_962.5</result>