A project has been defined to contain the following list of activities, along with their precedence relations and time and cost estimates for the activity durations. Use the normal durations to compute the earliest start (ES), earliest finish (EF), latest start (LS), latest finish (LF) and slack on each of the activities. In addition to the activity costs, there are also indirect costs of $1500 per week as well as a penalty cost of $2500 for every week the project is delayed past week 24. If the manager wants to minimize the total project costs, when should the project be delivered? a. 24 b. 22 c. 21 d. 23