A cuboid water tank is 20 cm long, 16 cm wide, and 18 meters deep. If a conical iron block with a bottom radius of 4 cm and a height of 15 cm is thrown into the water, how many centimeters will the water surface rise?
一个长方体水箱，长20厘米，宽16厘米，水深18匣米，现将一个底面半径4厘米，高15厘米的圆锥形铁块投入水中，水面上升多少厘米？
<gadget id="calculator">4 ** 2</gadget>
<output>16</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(1/3) / 20 / 16</gadget>
<output>1/960 = around 0.001042</output>

<gadget id="calculator">3.14 * 16 * 15 * (1/960)</gadget>
<output>0.785</output>

<result>0.785</result>