What is the surface area of a cylindrical object whose base diameter and height are both 4 cm?
一个圆柱形物体，它的底面直径和高都是4厘米，它的表面积是多少平方厘米．
<gadget id="calculator">3.14 * 4 * 4</gadget>
<output>50.24</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">50.24 + 25.12</gadget>
<output>75.36</output>

<result>75.36</result>