84 cm long iron wire is welded into a rectangular parallelepiped frame, its length is 8 cm, width is 7 cm, and its height is how many cm.
用84厘米长的铁丝正好焊成一个长方体框架，它的长是8厘米，宽是7厘米，高是多少厘米．
<gadget id="calculator">8 * 4</gadget>
<output>32</output>

<gadget id="calculator">7 * 4</gadget>
<output>28</output>

<gadget id="calculator">84 - 32 - 28</gadget>
<output>24</output>

<gadget id="calculator">24 / 4</gadget>
<output>6</output>

<result>6</result>