The circumference of the bottom of the cylinder is 6.28 cm, and the height is 5 cm. Find the volume?
圆柱底面周长6.28厘米，高5厘米，求体积？
<gadget id="calculator">6.28 / 3.14 / 2</gadget>
<output>1</output>

<gadget id="calculator">1 ** 2</gadget>
<output>1</output>

<gadget id="calculator">3.14 * 1 * 5</gadget>
<output>15.7</output>

<result>15.7</result>