A circle with a radius of 5 cm has a largest and smallest square inside and outside, and the area of the larger square is larger than the area of the smaller square by how many square centimeters.
半径为5厘米的圆内外各有一个最大和最小的正方形，大正方形的面积比小正方形的面积大多少平方厘米．
<gadget id="calculator">5 * 2</gadget>
<output>10</output>

<gadget id="calculator">10 * 10</gadget>
<output>100</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">4 * 5 * 5 * (1/2)</gadget>
<output>50</output>

<gadget id="calculator">100 - 50</gadget>
<output>50</output>

<result>50</result>