Cut a cylinder along the diameter of the bottom surface, the cross section is a square with side length 4 decimeters, what is the volume of this cylinder in cubic decimeters?
把一个圆柱体沿底面直径切开，横截面为一个边长4分米的正方形，这个圆柱体的体积是多少立方分米．
<gadget id="calculator">4 / 2</gadget>
<output>2</output>

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

<gadget id="calculator">3.14 * 4 * 4</gadget>
<output>50.24</output>

<result>50.24</result>