Cut a circle with a circumference of 31.4 cm into two semicircles, what is the circumference of each semicircle in cm?
把一个周长为31.4cm的圆剪成两个半圆，每个半圆的周长是多少cm．
<gadget id="calculator">31.4 / 2</gadget>
<output>15.7</output>

<gadget id="calculator">31.4 / 3.14</gadget>
<output>10</output>

<gadget id="calculator">15.7 + 10</gadget>
<output>25.7</output>

<result>25.7</result>