If the radius of the circle is reduced from 8 cm to 6 cm, how much does the area of the circle decrease by π square centimeters?
圆的半径从8cm减少到6cm，圆的面积减少了多少π平方厘米
<gadget id="calculator">6 ** 2</gadget>
<output>36</output>

<gadget id="calculator">64 - 36</gadget>
<output>28</output>

<result>28</result>