There is a bucket with a bottom radius of 3 decimeters, filled with water, and a cuboid iron block with a square bottom (side length 2 decimeters) submerged in the water. When all the iron blocks are taken out of the water, the water level in the bucket drops by 5 cm. How many decimeters is the length of this cuboid iron block? (retain one decimal place)?
有一只底面半径为3分米的水桶，桶内盛满水，并有一块底面是正方形(边长为2分米)的长方体铁块淹没在水中．当铁块从水中全部取出时，桶内的水面下降了5厘米，求这块长方体铁块的长有多少分米？(得数保留一位小数)？
<gadget id="calculator">3 ** 2</gadget>
<output>9</output>

<gadget id="calculator">3.14 * 9 * 0.5</gadget>
<output>14.13</output>

<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<gadget id="calculator">14.13 / 4</gadget>
<output>3.5325</output>

<result>3.5325</result>