cylinder, if cut along its diameter, its cross-section is a square with side length 3 decimeters, what is the surface area of this cylinder?
一个圆柱，如果沿着它的直径剖开，它的剖面是一个边长3分米的正方形，这个圆柱的表面积是多少？
<gadget id="calculator">3.14 * 3 * 3</gadget>
<output>28.26</output>

<gadget id="calculator">3 / 2</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">(3/2) ** 2</gadget>
<output>9/4 = around 2.25</output>

<gadget id="calculator">2 * 3.14 * (9/4)</gadget>
<output>14.13</output>

<gadget id="calculator">28.26 + 14.13</gadget>
<output>42.39</output>

<result>42.39</result>