The length of a section of iron sheet sewer pipe is 2.5m, the radius of the bottom surface is 1.5dm, and the joint is 2.5cm. How much iron sheet should be used to make this section of sewer pipe?
一节铁皮下水管长2.5m，底面半径1.5dm，接头处2.5cm，制作这节下水管至少要用多少铁皮．
<gadget id="calculator">1.5 * 10</gadget>
<output>15</output>

<gadget id="calculator">3.14 * 2 * 15</gadget>
<output>94.2</output>

<gadget id="calculator">94.2 + 2.5</gadget>
<output>96.7</output>

<gadget id="calculator">2.5 * 100</gadget>
<output>250</output>

<gadget id="calculator">96.7 * 250</gadget>
<output>24_175</output>

<result>24_175</result>