Uncle Wang’s house is going to be a cylinder-shaped fuel tank. It is known that the diameter of the bottom is 4 decimeters and the height is 5 decimeters. Please help Uncle Wang calculate how many square decimeters of iron sheets are needed at least?
王大伯家要做一个圆柱体形状的油箱，已知底面直径是4分米，高是5分米．请帮助王大伯算一算至少需要铁皮多少平方分米？
<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 * 2</gadget>
<output>25.12</output>

<gadget id="calculator">62.8 + 25.12</gadget>
<output>87.92</output>

<result>87.92</result>