A cuboid without a cover, the length is 2 times of the width, is high (2/3), and the sum of all edge lengths is 72 centimeters, add water to the cuboid, when the water-filled part appears for the second time and the opposite side is a square, What is the volume of water.
一个无盖长方体，长是宽的2倍，是高的(2/3)，所有棱长之和为72厘米，往长方体内加水，当装水部分第二次出现一组对面是正方形时，水的体积是多少．
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">9 * (2/3)</gadget>
<output>6</output>

<gadget id="calculator">9 * 6 * 6</gadget>
<output>324</output>

<result>324</result>