The look-out must be able（）full attention to the（）of a proper look-out．

单项选择题She（the vessel）shall if necessary（）and in any event navigate with extreme caution until danger of collision is over.

A.take all her way off
B.take her way all off
C.take her way off
D.take off her all way

单项选择题SAFE SPEED is defined as that speed where（）.

A.you can stop within your visibility range
B.you can take proper and effective action to avoid collision
C.you are traveling slower than surrounding vessels
D.no wake comes from your vessel

单项选择题In order for a stand-on vessel to take action in a situation，she must determine that the other vessel（）.

A.Is restricted in her ability to maneuver
B.Has sounded the danger signal
C.Is not taking appropriate action
D.Has not changed course since risk of collision was determined

单项选择题If your vessel is the stand-on vessel in a crossing situation（）.

A.You must keep your course and speed
B.You may change course and speed as the other vessel must keep clear
C.The other vessel must keep her course and speed
D.Both vessels must keep their course and speed

单项选择题If necessary to avoid collision or allow more time to（）the situation，a vessel shall slacken her speed or take all way off by stopping or reversing her means of propulsion．

A.access
B.process
C.profess
D.recess