Divide the base of a cylinder with a base diameter and a height of 4 cm into many sectors, then cut them apart and assemble them into an approximate cuboid, find the surface area of the cuboid.
把一个底面直径和高均为4厘米的圆柱底面分成许多许多的扇形，然后切开，拼成一个近似的长方体，求长方体的表面积．
<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">3.14 * 4 * 4</gadget>
<output>50.24</output>

<gadget id="calculator">4 * 2 * 2</gadget>
<output>16</output>

<gadget id="calculator">25.12 + 50.24 + 16</gadget>
<output>91.36</output>

<result>91.36</result>