根据《长途光缆波分复用（WDM）传输系统工程验收规范》，某WDM系统分波器第1波长通路的输入端口光功率电平值为-22dBm,输出端口光功率电平值为-28dBm，该分波器第1波长通路的插入损耗为（）dBm。
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Which statement is TRUE in an overtaking situation（）.
A. One vessel is approaching another vessel from more than 20° abaft the beam
B. It is the duty of the vessel being overtaken to get out of the way
C. Any later change of bearing between the two vessels shall not make the overtaking vessel a crossing vessel
D. All of the above
一级普通消防站消防员呼救器配备数量为（）。
A. 1个/人
B. 2个/人
C. 3个/人
D. 4个/人
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