Make a cuboid wooden box (without cover) for selling apples. Its length is 70 cm, width 50 cm, and height 30 cm. At least how many square meters of wooden boards are used to make this kind of box.
制作一种卖苹果用的长方体木箱(无盖)，它的长是70厘米，宽50厘米，高30厘米．做这种箱子至少用木板多少平方米．
<gadget id="calculator">50 * 30</gadget>
<output>1_500</output>

<gadget id="calculator">70 * 30</gadget>
<output>2_100</output>

<gadget id="calculator">1_500 + 2_100</gadget>
<output>3_600</output>

<gadget id="calculator">3_600 * 2</gadget>
<output>7_200</output>

<gadget id="calculator">70 * 50</gadget>
<output>3_500</output>

<gadget id="calculator">7_200 + 3_500</gadget>
<output>10_700</output>

<gadget id="calculator">10_700 / 10_000</gadget>
<output>107/100 = around 1.07</output>

<result>107/100 = around 1.07</result>