If a circular piece of paper is cut into two equal semicircles, their perimeters will increase by 6 cm in total. What is the area of the circle?
把一个圆形纸片剪成两个相等的半圆，它们的周长共增加6cm，这个圆面积是多少．
<gadget id="calculator">6 / 2 / 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>