An isosceles trapezoidal iron sheet, the length of the upper base is 8cm, the length of the lower base is 10cm, and the height is 6cm. It is used to cut into the largest circular piece. How much cm should be cut off?**2.
一个等腰梯形铁片，上底长8cm，下底长10cm，高为6cm，用来剪成一个最大的圆片，应剪去边角料多少cm**2．
<gadget id="calculator">8 + 10</gadget>
<output>18</output>

<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">18 * 3</gadget>
<output>54</output>

<gadget id="calculator">3 ** 2</gadget>
<output>9</output>

<gadget id="calculator">3.14 * 9</gadget>
<output>28.26</output>

<gadget id="calculator">54 - 28.26</gadget>
<output>25.74</output>

<result>25.74</result>