The volume of a cylinder is 12.56 cubic decimeters, the radius of the base is 2 decimeters, what is the height in decimeters.
圆柱的体积是12.56立方分米，底面半径是2分米，高是多少分米．
<gadget id="calculator">2 ** 2</gadget>
<output>4</output>

<gadget id="calculator">3.14 * 4</gadget>
<output>12.56</output>

<gadget id="calculator">12.56 / 12.56</gadget>
<output>1</output>

<result>1</result>