单项选择题
A.circle of equal altitude B.parallel of declination C.parallel of altitude D.vertical circle
A line of position derived from a loran reading is a se...
单项选择题A line of position derived from a loran reading is a section of a(n) （）.
A.straight line B.arc C.parabola D.hyperbola
A light used to signal passing intentions must be an （）...
单项选择题A light used to signal passing intentions must be an （）.
A.all-round yellow light only B.all-round white light only C.all-round blue light only D.alternating red and yellow light
A light signal consisting of three flashes means （）.A.I...
单项选择题A light signal consisting of three flashes means （）.
A.I am in doubt as to your actions B.My engines are full speed astern C.I desire to overtake you D.I am operating astern propulsion
