The signal for a fire emergency on an OSV is（）.

A.a 30 second on 30 second off alternating signal

B.the continuous blast of the ships whistle for not less than 10 seconds supplemented by the continuous ringing of the general alarm bells for not less than 10 seconds

C.an intermittent ringing of the general alarm for not less than ten seconds

D.announced over the PA system

FOCKE350小盒包装机组显示器（OPC）显示各种（）、统计数据、修改各种参数、进行各种状态的设置，指示操作人员或维修管理人员进行相关的工作。