The cafeteria makes an uncovered stainless steel bucket with a bottom diameter of 4 decimeters and a height of 5 decimeters. How many square decimeters of stainless steel plates should be used to make this bucket?
食堂做一个无盖的不锈钢水桶，底面直径4分米，高5分米，做这个水桶至少要用多少平方分米的不锈钢板？
<gadget id="calculator">3.14 * 4 * 5</gadget>
<output>62.8</output>

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

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

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

<gadget id="calculator">62.8 + 12.56</gadget>
<output>75.36</output>

<result>75.36</result>