If the circumference of the upper base of a cylinder is 12.56 cm, what is the radius of the lower base in cm?
一个圆柱的上底面周长是12.56cm，它的下底面的半径是多少cm．
<gadget id="calculator">12.56 / 3.14 / 2</gadget>
<output>2</output>

<result>2</result>