The sum of the volumes of a cylinder and a cone with the same base and height is 6.28cm**3, what is the difference in volume in cm**3.
等底等高的圆柱与圆锥，它们的体积之和是6.28cm**3，体积之差是多少cm**3．
<gadget id="calculator">3 + 1</gadget>
<output>4</output>

<gadget id="calculator">6.28 / 4</gadget>
<output>1.57</output>

<gadget id="calculator">6.28 - 1.57</gadget>
<output>4.71</output>

<gadget id="calculator">4.71 - 1.57</gadget>
<output>3.14</output>

<result>3.14</result>