If a cylinder with a height of 5 decimeters is cut into two equal parts along the diameter of the base, the surface area will increase by 40 decimeters squared. What is the volume of this cylinder in cubic decimeters?
一个高是5分米的圆柱体，沿底面直径切成相等的两部分，表面积就增加40平方分米，这个圆柱体的体积是多少立方分米？
<gadget id="calculator">40 / 2 / 5 / 2</gadget>
<output>2</output>

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

<gadget id="calculator">3.14 * 4 * 5</gadget>
<output>62.8</output>

<result>62.8</result>