A cylinder has a base circumference of 62.8 meters and a height of 5 decimeters, what is its lateral area in square meters?
一个圆柱，底面周长是62.8米，高5分米，它的侧面积是多少平方米．
<gadget id="calculator">5 / 10</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">62.8 * (1/2)</gadget>
<output>31.4</output>

<result>31.4</result>