Formulate integer programming model: A road construction firm seeks to assign its force optimally over the next 28- week period. They can be assigned to any combination of the following: For any number of 10-week periods, working for the state, and earning a profit of $3200/week. For any number of 6-week periods, working for the county, and earning a profit of $2900/week. For any number of 3-week periods, working for a private land developer, and earning $2750/week. For any number of weeks ,working on parking lot construction ,and earning $2550/week. However, if the firm does any work at all for either the state or county (or both), it is expected to contribute $7500 to the campaign fund of a certain anonymous political figure