1. [单选题]They went on ________ as usual
A. work
B. worked
C. works
D. working
2. [单选题]下列说法不正确的是：I、互见中，一艘机动船与一艘用机器推进的从事捕鱼的船舶航向相反相互驶近致有构成碰撞危险时，应执行对遇局面条款；II、互见中，一艘操纵能力受到限制的船舶与一艘限于吃水的船舶航向相反相互驶近致有构成碰撞危险时，应执行对遇局面条款；III、互见中，一艘操纵能力受到限制的船舶与一艘操纵能力受到限制的船舶航向相反相互驶近致有构成碰撞危险时，应执行对遇局面条款
A. I
B. I、II
C. II、III
D. I、II、III
3. [单选题]Before performing any maintenance on a hydraulic system storing energy in an accumulator, you should
A. pressurize the system to test for leaks
B. bleed off all pressure within the system
C. operate the machine until it reaches normal temperature
D. disconnect the pump pressure control switch
4. [单选题]Dry powder is used to put out ________
A. electrical fire
B. oil fire
C. common fires
D. all kinds of fires
5. [单选题]中版海图上所标注的水深当水深在21～31米时，精确到：()
A. 0.1m
B. 0.5m
C. 整米
D. 四舍五入
