The central angle of a sector is 60 degrees, the area of the circle it is in is 420cm**2, what is the area of the sector in cm**2.
一个扇形的圆心角是60度，它所在圆的面积是420cm**2，这个扇形的面积是多少cm**2．
<gadget id="calculator">60 / 360</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">420 * (1/6)</gadget>
<output>70</output>

<result>70</result>