A cylindrical piece of wood has a base diameter of 4 cm and a height of 20 cm. Dividing the piece of wood into two equal pieces from top to bottom along its base diameter and height, by how much does the surface area of this cylindrical piece of wood increase?
一根圆柱形状的木料，底面直径是4厘米，高是20厘米．沿着它的底面直径和高，从上到下把这块木料分成相等的两块，这根圆柱木料表面积增加了是多少？
<gadget id="calculator">4 * 20 * 2</gadget>
<output>160</output>

<result>160</result>