The central angle of a fan is 90°, and the radius is 8 cm. What is the area of the fan in square centimeters?
一个扇形圆心角是90°，半径是8cm，这个扇形的面积是多少平方厘米？
<gadget id="calculator">90 / 360</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">8 ** 2</gadget>
<output>64</output>

<gadget id="calculator">(1/4) * 3.14 * 64</gadget>
<output>50.24</output>

<result>50.24</result>