There is a steel pipe 4 meters long with an inner diameter of 4 decimeters and an outer diameter of 6 decimeters. What is the volume of this steel pipe?
有一根4米长的钢管，它的内直径4分米，外直径6分米，这根钢管的体积是多少？
<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">4 / 2</gadget>
<output>2</output>

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

<gadget id="calculator">3.14 * 9</gadget>
<output>28.26</output>

<gadget id="calculator">2 ** 2</gadget>
<output>4</output>

<gadget id="calculator">3.14 * 4</gadget>
<output>12.56</output>

<gadget id="calculator">28.26 - 12.56</gadget>
<output>15.7</output>

<gadget id="calculator">15.7 * 4 * 10</gadget>
<output>628</output>

<result>628</result>