A circular fountain with a diameter of 8 meters is surrounded by a railing, and a column is made every 1.57 meters of the railing. How many columns are needed for this fountain?
给一个直径8米的圆形喷水池围上栏杆，栏杆每隔1.57米做1个立柱．这个喷水池需要几个立柱？
<gadget id="calculator">8 / 1.57</gadget>
<output>5.095541</output>

<gadget id="calculator">3.14 * 5.095541</gadget>
<output>15.999999</output>

<result>15.999999</result>