A cylindrical bucket has an inner diameter of 4 decimeters and a depth of 5 decimeters. If 31.4 liters of water are poured into the bucket, what is the depth of the water in the bucket?
一个圆柱形水桶，桶内直径是4分米，桶深5分米，如果将31.4升的水倒入桶中，桶里水的深度占桶深的多少．
<gadget id="calculator">4 / 2</gadget>
<output>2</output>

<gadget id="calculator">2 ** 2</gadget>
<output>4</output>

<gadget id="calculator">3.14 * 4</gadget>
<output>12.56</output>

<gadget id="calculator">31.4 / 12.56</gadget>
<output>2.5</output>

<gadget id="calculator">2.5 / 5</gadget>
<output>0.5</output>

<result>0.5</result>