单项选择题
A. the angle between the horizontal and the line of sight to the visible horizon B. index error C. parallax D. terrestrial refraction
The height of a light is measured from which reference ...
单项选择题The height of a light is measured from which reference plane?（）
A.Mean low water B.Mean high water C.Average water level D.Geographical sea level
The Earth’s irregular heating is caused by （）.A.the tim...
单项选择题The Earth’s irregular heating is caused by （）.
A.the time of day B.the seasons C.geography D.All of the above
The Earth has the shape of a(n) （）.A.sphereB.oblate sph...
单项选择题The Earth has the shape of a(n) （）.
A.sphere B.oblate spheroid C.spheroid of revolution D.oblate eggoid
