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Under Rule 22 — Visibility of Lights, what should a navigator remember?
A
One short blast means starboard, two means port, three means astern propulsion, and five or more rapid blasts mean doubt or danger.
B
In restricted visibility, power-driven vessels making way sound one prolonged blast every 2 minutes.
C
Masthead light of large vessels must be visible at 6 miles.
D
The last vessel of a tow, if manned, shall where practicable sound one prolonged followed by three short blasts.