Every vessel should at all times proceed at a safe speed. Safe speed is defined as that speed where（）.

单项选择题Every vessel shall proceed at a safe speed（）the prevailing circumstances and conditions

A.adapted to
B.used by
C.liable to
D.adaptation to

单项选择题Every vessel shall at all times proceed at a safe speed so that she can（）.

A.take proper and effective action to avoid collision
B.be stopped within a distance appropriate to the prevailing circumstances and conditions
C.neither A nor B
D.both A and B

单项选择题As you approach Shreves cut-off you see Red River LandingGage (302.4 AHP) which reads 4.2 feet. Which of thefollowing statements is TRUE? （）

A.This reading is at the same elevation as the 6.2 ft. mark on the gage at Head of Passes
B.A vessel drawing 8 ft would be able to pass over the sill at Old River Lock
C.This reading is 6.4 feet below the Low Water Reference Plane
D.A vessel drawing 7 ft. would be able to pass through the locks at Lower Old River

单项选择题As you approach Kate Aubrey Bar Light (mile 788 AHP)，yoursearchlight will show what type of marking at the light? （）

A.Green square
B.Red and green banded square
C.Green triangle
D.Green diamond

单项选择题An overtaking situation would be one in which one vessel is approaching another from more than how many degrees abaft the beam? （）

A.0°
B.10°
C.22.5°
D.None of the above