The programme manager for Channel 10 would like to determine the best way to allocate the time for the 11:00-11:30 evening news broadcast. Specifically, she would like to determine the number of minutes of broadcast time to devote to local news, national news, weather and sports. Over the 30-minute broadcast, ten minutes are set aside for advertising. The station's broadcast policy states that at least 15 per cent of the time available should be devoted to local news coverage; the time devoted to local news or national news must be at least 50 per cent of the total broadcast time; the time devoted to the weather segment must be less than or equal to the time devoted to the sports segment; the time devoted to the sports segment should be no longer than the total time spent on the local and national news; and at least 20 per cent of the hould be devoted to the weather segment. The production costs per minute are 300 for local news, 200 for national news, 100 for weather and 100 for sports.

a. Formulate and solve a linear programme that can determine how the 20 available minutes should be used to minimize the total cost of producing the programme.

b. Interpret the dual price for the constraint corresponding to the available time. What advice would you give the station manager given this dual price?

c. Interpret the dual price for the constraint corresponding to the requirement that at least 15 per cent of the available time should be devoted to local coverage. What advice would you give the station manager given this dual price?

d. Interpret the dual price for the constraint corresponding to the requirement that the time devoted to the local and the national news must be at least 50 per cent of the total broadcast time. What advice would you give the station manager given this dual price?

e. Interpret the dual price for the constraint corresponding to the requirement that the time devoted to the weather segment must be less than or equal to the time devoted to the sports segment. What advice would you give the station manager given this dual price?