A cylindrical wooden block with a base diameter of 10 cm and a height of 8 cm is divided into two small cylinders along the cross-section. The surface area is increased by π square centimeters compared to the original one.
把一个底面直径为10厘米，高是8厘米的圆柱形木块，沿横截面分成两个小圆柱体表面积比原来增加多少π平方厘米．
<gadget id="calculator">10 / 2</gadget>
<output>5</output>

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

<gadget id="calculator">25 * 2</gadget>
<output>50</output>

<result>50</result>