A cylindrical oil barrel (with a cover) has a bottom diameter of 2.8 decimeters and a height of 40 centimeters. How many liters of oil can such an oil barrel hold?
一个圆柱形油桶(有盖)，底面直径是2.8分米，高是40厘米，做这样的一个油桶大约可以盛油多少升？
<gadget id="calculator">2.8 / 2</gadget>
<output>1.4</output>

<gadget id="calculator">1.4 ** 2</gadget>
<output>1.96</output>

<gadget id="calculator">40 / 10</gadget>
<output>4</output>

<gadget id="calculator">3.14 * 1.96 * 4</gadget>
<output>24.6176</output>

<result>24.6176</result>