The radius of a large circle is 4dm, and the diameter of a small circle is 2dm. How many square decimeters is the area of the large circle greater than the area of the small circle?
一个大圆的半径为4dm，一个小圆的直径为2dm，大圆的面积比小圆的面积多多少平方分米？
<gadget id="calculator">4 ** 2</gadget>
<output>16</output>

<gadget id="calculator">3.14 * 16</gadget>
<output>50.24</output>

<gadget id="calculator">2 / 2</gadget>
<output>1</output>

<gadget id="calculator">1 ** 2</gadget>
<output>1</output>

<gadget id="calculator">3.14 * 1</gadget>
<output>3.14</output>

<gadget id="calculator">50.24 - 3.14</gadget>
<output>47.1</output>

<result>47.1</result>