什么是浮阀板的液面落差?
“短声”指历时:() ["约1秒的笛声","约1~2秒的笛声","约2~3秒的笛声","约4~6秒的笛声"]
什么是塔板开孔率?
来船的红舷灯在东北方向消失,他船当时的船首向大约为:() ["337.5°或225°","157.5°或045°","180°或000°","135°或067.5°"]
本船航向010,在右舷45度处发现来船红灯消失而见到绿灯,则来船的航向约为:() ["337.5°或225°","235°","225°","337.5°"]
分馏塔塔板的作用是什么?