A cylindrical cake box has a base diameter of 6 cm and a height of 20 cm. At least how much cardboard is needed to make this pie box?
一个圆柱形的饼盒，底面直径是6厘米，高是20厘米．做这个饼盒至少要多少硬纸？
<gadget id="calculator">3.14 * 6 * 20</gadget>
<output>376.8</output>

<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">3 ** 2</gadget>
<output>9</output>

<gadget id="calculator">3.14 * 9 * 2</gadget>
<output>56.52</output>

<gadget id="calculator">376.8 + 56.52</gadget>
<output>433.32</output>

<result>433.32</result>