For a cylinder, if its height is shortened by 3 cm, its surface area will be reduced by 94.2 cm**2, and its volume will be reduced by how many cubic centimeters.
一个圆柱体，如果把它的高截短3厘米，表面积就减少94.2cm**2，体积减少了它的多少立方厘米．
<gadget id="calculator">94.2 / 3</gadget>
<output>31.4</output>

<gadget id="calculator">31.4 / 3.14 / 2</gadget>
<output>5</output>

<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">3.14 * 25 * 3</gadget>
<output>235.5</output>

<result>235.5</result>