A cylindrical tank with a radius of 3 decimeters holds water 4 decimeters deep. After an irregular iron block is fully immersed in it, the water level rises by 1 decimeter and the water does not overflow. The volume of the iron block How many cubic decimeters.
一个半径是3分米的圆柱形槽盛有4分米深的水，把一个形状不规则的铁块全部沉浸在里面后，水面上升了1分米，且水没有溢出，这个铁块的体积是多少立方分米．
<gadget id="calculator">3 ** 2</gadget>
<output>9</output>

<gadget id="calculator">3.14 * 9 * 1</gadget>
<output>28.26</output>

<result>28.26</result>