天文经纬度的基准是大地水准面，大地经纬度的基准是参考椭球面。在大地原点处，大地水准面与参考椭球面相切，其天文经纬度分别等于其大地经纬度。“1954北京坐标系”的大地原点在哪里？“1980西安坐标系”的大地原点在哪里？

远程教育的决定性特征是教的行为和学的行为在时空上分离。

Every deliberate act of wrongdoing by the master or any of the crew against the ship or cargo，without the authorization or privity of the Shipowner or his agent，is（）.

（）, or drum is used for hauling in or letting out the wires or ropes which will fasten the ship to the shore.

A salvor may be（）the whole or part of the payment due under Salvage Convention to the extent that the salvage operations have become necessary or more difficult because of fault or neglect on his part or if the salvor has been guilty of fraud or other dishonest conduct.

The （） is used for hauling in or letting out the wires or ropes.

Vessels must be（）valid certificate of nationality or certificated of registry or license.

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

我国现行的大地原点、水准原点分别位于（）。

华北水利水电大学（花园校区）位于（）。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

在大地测量、城市和矿山测量、建筑物变形测量、水下地形测量等方面得到广泛的应用的测量仪器是()。