A pair of glass jars without a cover, the length is 5dm, the width and height are both 4dm, at least how much glass dm**2 is needed to make the pair of glass jars.
一对无盖的玻璃缸，长是5dm，宽和高都是4dm，做这对玻璃缸至少需要玻璃多少dm**2．
<gadget id="calculator">5 * 4</gadget>
<output>20</output>

<gadget id="calculator">4 * 4</gadget>
<output>16</output>

<gadget id="calculator">20 + 16</gadget>
<output>36</output>

<gadget id="calculator">36 * 2</gadget>
<output>72</output>

<gadget id="calculator">72 + 20</gadget>
<output>92</output>

<gadget id="calculator">92 * 2</gadget>
<output>184</output>

<result>184</result>