The radius of a sector is 5cm, and the central angle is 60°, then the area of the sector is: how many cm**2.
一扇形的半径是5cm，圆心角是60°，则此扇形的面积是：多少cm**2．
<gadget id="calculator">25 / 6</gadget>
<output>25/6 = around 4.166667</output>

<result>25/6 = around 4.166667</result>