If a conical wood with a base radius of 10 decimeters and a height of 5 decimeters is cut into two equal halves vertically along the height, how many square decimeters will the surface area increase?
把一个底面半径10分米，高5分米的圆锥形木料，如果沿着高垂直切成相等的两半，表面积增加了多少平方分米．
<gadget id="calculator">5 / 2</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">2 * 10 * (5/2) * 2</gadget>
<output>100</output>

<result>100</result>