A 3.2-meter-long bamboo pole is vertically inserted into a swimming pool with a water depth of 1.8 meters. How much shorter is the part above the water than the part entering the water?
一根3.2米长的竹竿垂直插入水深为1.8米的游泳池中，露出水面部分至少比入水部分短多少米？
<gadget id="calculator">3.2 - 1.8</gadget>
<output>1.4</output>

<gadget id="calculator">1.8 - 1.4</gadget>
<output>0.4</output>

<result>0.4</result>