In the horizon system of coordinates what is equivalent to latitude on the Earth?（）.

In the horizon system of coordinates what is equivalent to the equator on the Earth?（）.

A.Prime vertical circle
B.Principal vertical circle
C.Parallels of altitude
D.Horizon

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In order for a star to be used for a sight at lower transit，the star must（）.

A.be circumpolar
B.have a declination equal to or greater than your latitude
C.have a GHA of 180°
D.have the SHA equal to or less than the LHA

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