Cut out the largest circle from a rectangular piece of paper with a width of 3 cm, what is the area of the circle in cm**2.
在宽为3cm的长方形纸片中剪去一个最大的圆，则圆的面积是多少cm**2．
<gadget id="calculator">3 / 2</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">(3/2) ** 2</gadget>
<output>9/4 = around 2.25</output>

<gadget id="calculator">3.14 * (9/4)</gadget>
<output>7.065</output>

<result>7.065</result>