Build a cylindrical biogas pit with a bottom diameter of 3 meters and a depth of 2 meters. How many cubic meters of biogas can this biogas pit hold? (π takes 3.14)
砌一个圆柱形的沼气池，底面直径是3米，深2米，这个沼气池可以容纳多少立方米的沼气．(π取3.14)
<gadget id="calculator">3 / 2</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">(3/2) ** 2</gadget>
<output>9/4 = around 2.25</output>

<gadget id="calculator">3.14 * (9/4) * 2</gadget>
<output>14.13</output>

<result>14.13</result>