i need question 3 only....

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A plan for detection of C-virus outbreak is being developed in a country. The plan is to inspect all the cities efficiently. In order to inspect the cities, the following procedure is followed: Teams capable of investigating the virus will set up medical hubs in some of the cities (say, hub-city). Each team will first inspect its hub-city, then the neighbor cities are inspected. Cities that are not neighbors to the hub city cannot be inspected by a team (that is, in order for a city to be inspected it should have a hub or it should be neighbor to a hub city). After inspecting a non-hub city, the team will immediately go back to the hub-city for replenishment. After replenishment, they move to the next neighbor city. The objective of this plan to find the minimum number of teams such that all the cities are inspected within a day. The following sets and parameters are given: I: Set of cities, I = (1, ...,N). nij: A binary parameter, which is equal to one when city i is neighbor of city j, and zero otherwise; where i, jel, Tij: Travel time in hours from city i to city j; where i, j el, S: Total time needed in hours to inspect city i, R: Replenishment time in hours. Answer the following three questions: QI. Suggest what variables you will use to model the above scenario? Do not write the complete definition. Just mention (in words) the possible variables. Q2. Describe the possible constraints that should be used in the mathematical model? Do not write the complete constraints. Just mention in words) the possible constraints. Q3. Define all variables and parameters clearly. Build an implicit or compact (see note below for definition of "im- plicit") mathematical model that captures the above scenario. Note: In Q3, write an implicit model, that is, use summation (2) and enumeration (V) symbols wherever possible. For summation symbols, specify the limits of the summation. If you use enumeration symbol, make sure the index range is clearly defined in your solution. You can add new variables or parameters for the questions. Whenever a new parameter is used, it must be clearly defined. Whenever a new variable is used, it must be clearly defined and connected