In the physical education class, the teacher draws a circle on the playground with a 5-meter-long rope wrapped around a wooden stake. What is the diameter of the circle in meters?
体育课上老师用一根长5米的绳子绕着一根木桩在操场上画圆，这个圆的直径是多少米．
<gadget id="calculator">5 * 2</gadget>
<output>10</output>

<result>10</result>