In a $0-1$ integer programming model, if the constraint $x_1-x_{2}0,$ it means if project $2$ is selected, project $1.$The Biggs Department Store chain has hired an advertising firm to determine the types and amount of

advertising it should invest in for its stores. The three types of advertising available are television and

radio commercials and newspaper ads. The retail chain desires to know the number of each type of

advertisement it should purchase in order to maximize exposure. It is estimated that each ad or

commercial will reach the following potential audience and cost the following amount:

The company must consider the following resource constraints:

The budget limit for advertising is $$100,000.$

The television station has time available for $6$ commercials.

The radio station has time available for $10$ commercials.

The newspaper has space available for $5$ ads.

The advertising agency has time and staff available for producing no more than a total of $12$

commercials and$/$or ads.

The number of Newspaper ads cannot be more than twice the number of Radio commercials.

Choose the option below that best represents the empty space above.

must be selected

must not be selected

None of the above