A cylindrical water tank has an inner diameter of 20cm and a depth of 30cm. When an iron block is submerged in the water, the water level rises (1/3). The iron block weighs 7.8 grams per cubic centimeter. Find the weight of this iron block?
一个圆柱形水缸内直径是20cm，深30cm，把铁块没入水中，水面上升(1/3)，每立方厘米铁块重7.8克，求这个铁块的重量？
<gadget id="calculator">20 / 2</gadget>
<output>10</output>

<gadget id="calculator">10 ** 2</gadget>
<output>100</output>

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

<gadget id="calculator">3.14 * 100 * 30 * (1/3)</gadget>
<output>3_140</output>

<gadget id="calculator">7.8 * 3_140</gadget>
<output>24_492</output>

<result>24_492</result>