4.1) Please follow the 5 steps: 1)Problem Data. 2)Decision variables. 3)Objective Function. 4)Constraints. 5)Optimization Model.

4. Integer Programming Models. (15 points modeling+5 points question) My cell phone has three different SIM cards, each of them associated with a different company: SIM card 1 is associated with company A, SIM card 2 is associated with company B, and SIM card 3 is associated with company C (SIM cards association cannot be changed). Company A charges me $16 fixed a month, and $0.25 per minute of call. Company B charges me $25 fixed a month, and $0.21 per minute of call. Company C charges me $18 fixed a month, and $0.22 per minute of call. I need to make calls for at least 200 minutes every month. If I don't pay the fixed charge of a company, I cannot make calls with this company. I can use any combination of companies to make all the calls I require. I need some help to minimize my cell phone bill. 4.1) Following the 5 steps introduced in class, model the above problem. Do not solve