In reduced visibility，you hear two prolonged blasts of a whistle. This signal is sounded by a （）.

单项选择题In order to maintain speed while changing course from a close reach to a broad reach，the sails should be（）.

A.lowered
B.reefed
C.hauled in
D.eased out

单项选择题In order for a vessel to be engaged in fishing she must be（）.

A.underway
B.using gear which extends more than 50 meters outboard
C.using a seine of some type
D.using gear which restricts her maneuverability

单项选择题In fog you observe your radar and determine that risk of collision exists with a vessel which is 2 miles off your port bow. You should（）.

A.stop your engines
B.sound the danger signal at two-minute intervals
C.hold course and speed until the other vessel is sighted
D.take avoiding action as soon as possible

单项选择题In determining safe speed，the Rules list all of the following as factors which must be taken into account EXCEPT the（）.

A.limitations of radar equipment
B.presence of background lights at night
C.maximum horsepower of your vessel
D.maneuverability of your vessel

单项选择题In determining if risk of collision exists the following considerations shall be among（）.

A.these taken into calculation
B.those taking into account
C.that taken into account
D.those taken into account