You have been hired to prepare the Christmas campaign of a toys store. The manager explains you how they want to organise the campaign: The manager is concerned with the days between December 23 and January 5, and in particular the days with high attendance of people (category A: maximum demand; and category B: average demand). Holidays and low demand days are not studied. Category A days are: 24/12; 27/12; 31/12; 03/01 and 05/01 90 customers/hour. Category B days are: 23/12; 30/12 and 02/01 50 customers/hour. Staff must work 4 of the 5 days of category A and 2 of the 3 days of category B. The cost of all hired staff is considered the same. A person cannot work the three most important dates: 24/12, 31/12 and 05/01. Customers are divided into two groups. On the one hand, there are customers who make the purchase in person (CP): they enter the store, talk to the staff and end up buying. On the other hand, there are customers who order online (CO) and only have to pick up the order. The average duration is estimated to be 10 minutes for each CP and 4 minutes for each CO. Based on data from previous campaigns, it is estimated that 40% of the customers are CO. Any person hired can serve both groups of customers indistinctly. a. How many people should work in one day of category A? And for B? b. Determine the feasible patterns (working days) according to the conditions stated. c. Develop the mathematical model to solve this situation.