单选题 The recommended course changes ______ prevent ships from turning into each other.

单选题 The technique of taking of compass bearings depends on ______.

单选题 The vessel's operator cannot establish a safe speed ______ knowing how far the vessel will travel before stopping, for any normal loading condition or speed.

单选题 In some cases, the vessel ______ enough for the rudder to effect a turn promptly.

单选题 ______ good a radar set might be, the range scale selected determines the nature of the information available to the operator.

单选题 Radar plotting is required by Rule 7. Plotting is not required ______ "equivalent systematic observation" is used.

单选题 ______ excessive speed is not the most glaring cause of maritime accidents, there have been very few collisions between stopped vessels.

单选题 A vessel that has ample clearance when moving slowly through shallow water ______.

单选题 ______ there is doubt, you must assume that risk of collision does exist.