Put some water in a cylindrical measuring cup with a base diameter of 6 cm and a height of 10 cm. The water surface is 7 cm high. At this time, a conical decorative piece is immersed in the water, and the water surface just rises to the mouth of the cup. What is the volume of this conical decorative piece?
在一个底面直径是6厘米、高10厘米的圆柱形量杯里放些水，水面高7厘米．这时把一个圆锥形装饰件沉浸到水中，水面正好上升到杯口，这个圆锥形装饰件的体积是多少？
<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">3 ** 2</gadget>
<output>9</output>

<gadget id="calculator">10 - 7</gadget>
<output>3</output>

<gadget id="calculator">3.14 * 9 * 3</gadget>
<output>84.78</output>

<result>84.78</result>