If a cylinder with a base radius of 6 decimeters and a height of 2 meters is cut along the line connecting the centers of the upper and lower bases, how many square decimeters will its surface area increase?
把一个底面半径是6分米、高2米的圆柱，沿着上下底面的圆心连线把它切开后，它的表面积增加了多少平方分米．
<gadget id="calculator">2 * 10</gadget>
<output>20</output>

<gadget id="calculator">6 * 2 * 20 * 2</gadget>
<output>480</output>

<result>480</result>