A cylindrical wooden barrel has a base diameter of 6 decimeters and a ratio of height to radius of 3:1. What is the volume of this oil barrel?
一个圆柱形木桶，底面直径6分米，高与半径的比是3：1，这个油桶的体积是多少？
<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">3 ** 2</gadget>
<output>9</output>

<gadget id="calculator">3.14 * 9 * 3 * 3</gadget>
<output>254.34</output>

<result>254.34</result>