Xiao Ming uses a semicircular paper with a radius of 6 decimeters to form the side of a cone. At this time, a circular paper with an area of how many square decimeters is needed to make a complete cone.
小明用一个半径6分米的半圆形纸围成一个圆锥的侧面，此时要配上一个面积是多少平方分米的圆形纸才能做成一个完整的圆锥．
<gadget id="calculator">3.14 / 2 / 3.14 / 2</gadget>
<output>0.25</output>

<gadget id="calculator">6 * 0.25</gadget>
<output>1.5</output>

<gadget id="calculator">1.5 ** 2</gadget>
<output>2.25</output>

<gadget id="calculator">2.25 * 3.14</gadget>
<output>7.065</output>

<result>7.065</result>