To make a cuboid carton with a length of 0.8 meters, a width of 0.6 meters and a height of 0.4 meters, how many square meters of cardboard are needed to make this carton.
做一个长方体的纸箱，长0.8米，宽0.6米，高0.4米，做这个纸箱至少需要纸板多少平方米．
<gadget id="calculator">0.8 * 0.6</gadget>
<output>0.48</output>

<gadget id="calculator">0.8 * 0.4</gadget>
<output>0.32</output>

<gadget id="calculator">0.6 * 0.4</gadget>
<output>0.24</output>

<gadget id="calculator">0.48 + 0.32 + 0.24</gadget>
<output>1.04</output>

<gadget id="calculator">1.04 * 2</gadget>
<output>2.08</output>

<result>2.08</result>