A cuboid iron sheet water tank (without a cover) for storing live fish is 1.1 meters long, 0.8 meters wide and 0.5 meters high. What is the minimum square meter needed to make this water tank?
存放活鱼的长方体铁片水箱(上面没有盖)，长1.1米，宽0.8米，高0.5米．做这个水箱至少要用多少平方米？
<gadget id="calculator">1.1 * 0.8</gadget>
<output>0.88</output>

<gadget id="calculator">1.1 * 0.5 * 2</gadget>
<output>1.1</output>

<gadget id="calculator">0.8 * 0.5 * 2</gadget>
<output>0.8</output>

<gadget id="calculator">0.88 + 1.1 + 0.8</gadget>
<output>2.78</output>

<result>2.78</result>