A rectangular parallelepiped glass cylinder is 30 cm long and 20 cm wide, filled with water at a height of 15 cm. After putting an iron block into the water (completely submerged in the water without overflowing), the water level rises to 18 cm. What is the volume of this iron block in cubic centimeters?
一个长方体玻璃缸，长30厘米，宽20厘米，里面装有15厘米高的水，将一个铁块放入后(完全浸入水中，且水未溢出)，水面升高到18厘米．这个铁块的体积是多少立方厘米？
<gadget id="calculator">18 - 15</gadget>
<output>3</output>

<gadget id="calculator">30 * 20 * 3</gadget>
<output>1_800</output>

<result>1_800</result>