Two security personnel were patrolling on a bridge. They started from the same point on the bridge at the same time, walked to both ends of the bridge, and returned immediately after reaching the bridge head. After 36 minutes, they met. If the speed of safety officer A is 70 m/min and the speed of safety officer B is 80 m/min, what is the length of the bridge in meters?
两名安全人员在一座大桥上巡视，两人同时从桥上的同一点出发，分别向桥的两端走去，到桥头后立即返回，经过36分钟两人相遇．如果甲安全员的速度是70米/分，乙安全员的速度是80米/分，这座大桥的长是多少米？
<gadget id="calculator">70 + 80</gadget>
<output>150</output>

<gadget id="calculator">36 / 2</gadget>
<output>18</output>

<gadget id="calculator">150 * 18</gadget>
<output>2_700</output>

<result>2_700</result>