Use the following scenario and data for questions $41$ to $50$

A car dealership decided to add an annex to its sales office as a customer bunge. The project is divised into the

acthities listed in the following table. The immediate predecessar$($s$),$ times and costs, both nomal and crashed,

are given. To finish the project sooner, the dealership has to mabe time and cost tradeotfs. If the project needs to

be finished in $25$ weeks, you are required to farmulate a linear programming model to decide about how much to

crash for each acthity.

To answer the following questions, you may want to use the last column of the following table to compute the cast

of crashirg an activity by one week.

$x_{i}0,y_{i}0$ for all $i-A,B,C,D,E,F,G,II$

min $300x_A+600x_B+700x_C+400x_D+125x_B+200x_B+250x_C+300x_B$

$x_{t}0,y_{r}0$ for all $i=A,B,C,D,E.F,G,H$

none of the above.