If a cylindrical piece of wood with a length of 3 meters and a base radius of 5 centimeters is sawed into two pieces, the surface area will be increased by how many square centimetres.
把一根长3米，底面半径5厘米圆柱形木料锯成两段，表面积增加多少平方厘米．
<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">3.14 * 25 * 2</gadget>
<output>157</output>

<result>157</result>