Automatic identification systems (AIS) are required to（）.
A. provide safety-related information automatically to shore stations，other vessels and aircraft
B. receive safety-related information automatically from similarly equipped vessels
C. exchange safety-related information with shore-based facilities
D. All of the above
查看答案
第三代路由器和第四代路由器最大的区别在于，第四代路由器开始使用交换矩阵。
A. 正确
B. 错误
山楂治食积气滞脘腹胀痛较甚者，宜配伍（）
A. 番泻叶
B. 青皮
C. 枳实
D. 当归
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