In plotting a running fix，how many fixed objects are needed to take your lines of position from? （）

单项选择题At the magnetic equator there is no induced magnetism in the vertical soft iron because（）.

A.the lines of force cross the equator on a 0°-180°alignment
B.the quadrantal error is 0°
C.there is no vertical component of the Earth's magnetic field
D.the intercardinal headings have less than 1°

单项选择题A vessel’s position should be plotted using bearings of（）.

A.buoys close at hand
B.fixed known objects on shore
C.buoys at a distance
D.All of the above

单项选择题A single line of position combined with a dead-reckoning position results in a(n)（）.

A.running fix
B.fix
C.estimated position
D.assumed position

单项选择题A relative bearing is always measured from（）.

A.true north
B.magnetic north
C.the vessel's beam
D.the vessel's head

单项选择题A position that is obtained by using two or more intersecting lines of position，taken at nearly the same time，is a(n)（）.

A.estimated position
B.fix
C.running fix
D.dead-reckoning position