Physics
Holography is a technique of

Recording a permanent three dimensional black and white photograph
Recording a permanent, sharp two diimensional black and white or multicolour photograph
Recording a permanent three dimensional multicolour photograph
Recording a permanent three dimensional photograph of a given single colour or a multicolour

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Physics
RADAR is used for:

locating geostationary satellites.
locating submerged submarines.
receiving a signals in a radio receiver.
detecting and locating the position of objects such as Aeroplanes.

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