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QUESTION TWO [Total mark allocated: 25] The pre-production models In the pre-production stages of the manufacturing of a piece of equipment that contains both electrical and mechanical parts, the following procedure is carried out: The specification is agreed, after which the design department makes a proto-type for approval, by the sales department. This prototype is in a form final enough for the later detailed mechanical and electrical design work to proceed independently. Once the detailed design work is complete, further sets of both electrical and mechanical parts are made which are then assembled together to form a series of complete pre-production models (PPMs). Note: the PPMs require both electrical and mechanical parts. Enough PPMs are made for electrical and mechanical proving tests to be carried out independently, although both proving tests require special test gear to be made. The manufacture of this test gear can be undertaken once the detailed development is complete. Electrical and mechanical proving tests having been completed, a final approval is given that enables materials to be ordered and production equipment to be made. Once all the material and production equipment is to hand, manufacture can start. Activities involved Duration (days) Agree specification Make prototype Prototype approved Detailed mechanical design 12 Detailed electrical design 10 Make mechanical parts for PPMs 6 Make electrical parts for PPMs Make mechanical test gear 15 Make electrical test gear 10 Make pre-production models (PPMs) Electrical proving test PPMs 10 Mechanical proving test PPMs Final approval given Make production equipment 15 Obtain production material Manufacture 15 Questions Answer the following questions. 2.1 Draw the network. [10 marks] 2.2 Analyse the network. [10 marks] 2.3 List those activities which, 35 days after work has started must: (a) have been finished (b) have been started if the total project time is not to be increased. [5 marks]