A cylindrical part tube is 70 cm long, the diameter of the outer cylinder is 20 cm, and the diameter of the inner cylinder is 10 cm. What is the volume of this part in cubic centimeters?
一根圆柱形的零件管，长70厘米，外圆柱直径为20厘米，内圆柱直径为10厘米，这个零件的体积是多少立方厘米．
<gadget id="calculator">20 / 2</gadget>
<output>10</output>

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

<gadget id="calculator">3.14 * 100 * 70</gadget>
<output>21_980</output>

<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">3.14 * 25 * 70</gadget>
<output>5_495</output>

<gadget id="calculator">21_980 - 5_495</gadget>
<output>16_485</output>

<result>16_485</result>