C45 or C-45 may refer to:
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Beech C-45 Expeditor, an American military transport aircraft
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C4.5 algorithm
C4.5 is an algorithm used to generate a decision tree developed by Ross Quinlan. C4.5 is an extension of Quinlan's earlier ID3 algorithm. The decision trees generated by C4.5 can be used for classification, and for this reason, C4.5 is often referr ...
, used to generate a decision tree
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C45 road (Namibia)
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Caldwell 45, a spiral galaxy
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Cannabis Act introduced as Bill C-45 to the Parliament of Canada
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EADS/Northrop Grumman KC-45, a cancelled air refueling aircraft for the US Air Force
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Scotch Game, a chess opening
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Underground Work (Women) Convention, 1935 of the International Labour Organization
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Ursus C-45, a Polish tractor
* C45, a variant of
Claridge Hi-Tec/Goncz Pistol rifle
* C45, a 45-minute audio
Compact Cassette
The Compact Cassette or Musicassette (MC), also commonly called the tape cassette, cassette tape, audio cassette, or simply tape or cassette, is an analog magnetic tape recording format for audio recording and playback. Invented by Lou Ottens ...
tape
* C45 Scaphandre Autonome,
vintage scuba equipment
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