cylinder with a height of 4 cm is cut into several equal parts vertically along its height and assembled into an approximate cuboid. The surface area is increased by 40 cm2. What is the volume of this cylinder in cubic centimeters?
将一个高为4厘米的圆柱沿它的高竖切成若干等份后拼成一个近似的长方体，表面积增加了40平方厘米，这个圆柱的体积是多少立方厘米？
<gadget id="calculator">40 / 2 / 4</gadget>
<output>5</output>

<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">3.14 * 25 * 4</gadget>
<output>314</output>

<result>314</result>