In a circle with a diameter of 10 cm, after cutting off the largest square, what is the remaining area in cm**2.
在一个直径10厘米的圆中，截取掉一个最大的正方形后，剩下的面积是多少cm**2．
<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">3.14 * 25</gadget>
<output>78.5</output>

<gadget id="calculator">5 / 2</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">10 * (5/2) * 2</gadget>
<output>50</output>

<gadget id="calculator">78.5 - 50</gadget>
<output>28.5</output>

<result>28.5</result>