If a cylinder with a base diameter of 4 decimeters is cut in half along its diameter, the surface area increases by 24 square decimeters. What is the volume of the cylinder?
一个底面直径为4分米的圆柱体沿直径剖成两半后，表面积增加了24平方分米，这个圆柱的体积是多少．
<gadget id="calculator">4 / 2</gadget>
<output>2</output>

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

<gadget id="calculator">24 / 2 / 4</gadget>
<output>3</output>

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

<result>37.68</result>