The side view of a cylinder is a rectangle. The length of the rectangle is 12.56 meters and the width is 3 meters. What is its maximum volume?
一个圆柱的侧面展开图是一个长方形，长方形的长是12.56米，宽是3米，它的体积最大是多少？
<gadget id="calculator">12.56 / 3.14 / 2</gadget>
<output>2</output>

<gadget id="calculator">2 ** 2</gadget>
<output>4</output>

<gadget id="calculator">3.14 * 4 * 3</gadget>
<output>37.68</output>

<result>37.68</result>