单项选择题
A.Maintain balance and move with agility
B.Climb up and down vertical ladders and stairways
C.Open and close watertight doors
D.Take part in vessel evacuation procedures
单项选择题 The information regarding ports such as buoyed channels,fairway,location and number of terminals,river channels,details of navigational marks,location of overhead bridges, underground cables etc. are shown in（）
单项选择题 On a weather map,a large letter “h” means（）
单项选择题 There are often three parts in a weather report, not including（）