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The assignment is for individual work. Any similarity between different submitted works will be investigated for plagiarism according to the University’s policy.  Handwritten solutions will not be accepted. Please write your answers clearly using MS Word or LaTeX with font size 11 or 12 and then convert it to a PDF file. Make sure that each sheet has your University ID Number and the question number(s). The main body of your work should NOT exceed 3 pages.  You can present your Excel Solver models (as screenshots) for reference in an appendix. The appendix will NOT be marked.  Use Excel Solver whenever needed, but do not include your Excel spreadsheet(s) as an answer of any question. If necessary, your spreadsheet will be requested later for checking.  Submit your work online (in PDF format) on or before 12:00 noon, Thursday, 14 Nov 2019 via my.wbs No other submission method will be accepted. Penalty for late submissions applies automatically.  An online forum will be open for requests for clarification on the assignment, but no requests will be accepted within 24 hours of the submission deadline. Question 1 [50%] SilverStone car company has decided to produce a limited-edition race car. The main parts of this car would be produced in a week at a special machine shop with contractors (from Monday to Sunday). There are two types of contractors; type A and type B. These contractors can be assigned to work at any day of the week. When a contractor of type A starts to work, s/he will work three days consecutively and cannot work more than three days a week. Similarly, when a contractor of type B starts to work, s/he will work two days consecutively and cannot work more than two days a week. For instance, if a contractor of type A starts to work on Wednesday, s/he will work on Wednesday, Thursday and Friday and will not return to work. On the other hand, if a contractor type B starts to work on Wednesday, s/he will work on Wednesday and Thursday and will not return to work. If a contractor starts to work on Saturday or Sunday, s/he will work for the required days since the prototype car production will end at the end of Sunday. For instance, if a contractor of type A starts to work on Saturday, s/he will only work on only Saturday and Sunday. The company can hire as many contractors as required with no constraints. However, due to production plan, the requirement of contractors for each day is different. The following table shows the number of required contractors (type is not important since they work on the same process) at each day. In addition, only one type of contractor should be working on Wednesday, either type A or type B but not both. There is no such a restriction for the other days. Due to the high workload on Thursday, the company would like to work with both contractor of type A and type B on Thursday. Monday Tuesday Wednesday Thursday Friday Saturday Sunday Required number of Contractors 40 30 20 60 25 35 50 2 of 2 The cost of type-A and type-B contractors is the same. Therefore, SilverStone car company wants to minimize the total number of contractors (type A and type B) hired for the production of race car. Part 1.1 [30%]: By considering the information given in the above problem, formulate and solve an integer programming model to determine the number of contractors assigned to produce this race car. Present both the problem formulation and the solution. Part 1.2 [20%]: Considering the required resources on each day, analyze the optimal solution of your model. What do you think about the applicability of your assignment schedule? Would it be possible to improve the schedule? If possible, what would be your modelling approach? Explain your approach and findings.