A piece of conical wood with a base diameter of 10 cm and a height of 15 cm is cut from the apex along the height into two pieces of the same shape and size. How much does the surface area increase?
一块底面直径是10厘米，高是15厘米的圆锥形木料，从顶点沿着高切成形状、大小完全相同的两块，表面积增加了多少．
<gadget id="calculator">15 / 2</gadget>
<output>15/2 = around 7.5</output>

<gadget id="calculator">10 * (15/2) * 2</gadget>
<output>150</output>

<result>150</result>