A cylindrical glass with a bottom circumference of 3.14dm contains some water, which occupies exactly two-fifths of the capacity of the glass. Put two iron blocks of the same size into a cup and submerge them in water. At this time, the water level rises by 6 cm, just level with the mouth of the glass. Find the volume of the glass.
一个底面周长是3.14dm的圆柱形玻璃杯内盛有一些水，恰好占杯子容量的五分之二．将两个同样大小的铁块放入杯子中，浸没在水里．这时水面上升6厘米，刚好与杯子口平齐，求玻璃杯的容积．
<gadget id="calculator">31.4 / 3.14 / 2</gadget>
<output>5</output>

<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">6 / (3/5)</gadget>
<output>10</output>

<gadget id="calculator">3.14 * 25 * 10</gadget>
<output>785</output>

<result>785</result>