Additional question: Aunt Wang’s cabinet-type air conditioner is 0.4 meters long, 0.2 meters wide, and 1.7 meters high. In order to prevent dust, Aunt Wang is going to make a cuboid cover with cloth to cover the air conditioner. Please do the calculation for her. How many square meters of cloth do you need at least for a cover? (neglected at joints)
附加题：王大妈家的柜式空调长0.4米，宽0.2米，高1.7米，为了防灰尘，王大妈准备用布做一只长方体套子把空调罩起来，请你帮她算下，做这只套子至少需要用多少平方米的布？(接头处忽略不计)
<gadget id="calculator">0.4 * 0.2</gadget>
<output>0.08</output>

<gadget id="calculator">0.4 * 1.7 * 2</gadget>
<output>1.36</output>

<gadget id="calculator">0.2 * 1.7 * 2</gadget>
<output>0.68</output>

<gadget id="calculator">0.08 + 1.36 + 0.68</gadget>
<output>2.12</output>

<result>2.12</result>