The diameter of a round coffee table top is 1m, what is its area in square meters?
一个圆形茶几桌面的直径是1m，它的面积是多少平方米？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(1/2) ** 2</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">3.14 * (1/4)</gadget>
<output>0.785</output>

<result>0.785</result>