If the radius of a circle is increased by 1.25m, how much does the circumference of the circle increase in m?
如果把一个圆的半径增加了1.25m，那么圆的周长就增加了多少m
<gadget id="calculator">2 * 3.14 * 1.25</gadget>
<output>7.85</output>

<result>7.85</result>