A cylinder is cut through the center of the bottom surface and divided into two parts along the height. The surface area increases by 40 square centimeters. It is known that the height of the cylinder is 5 centimeters. What is the original volume of the cylinder in cubic centimeters?
一个圆柱过底面圆心沿高切开分成两块，表面积增加了40平方厘米，已知圆柱的高是5厘米，则原来这个圆柱的体积是多少立方厘米．
<gadget id="calculator">40 / 2 / 5</gadget>
<output>4</output>

<gadget id="calculator">4 / 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>