Problem Statement: Project Crashing Consider a project with 6 activities, A through H. The following table contains the normal duration (in days), normal cost, crash duration (in days) and crash cost of all activities, as well as the cost slope (positive part) of all activities. The project's AON network diagram is shown below with the normal durations of the activities filled in the boxes. You are invited to crash this project based on the data given in the table and network diagram above. Answer the following questions. Before crashing the project, please identify all critical path(s). Please select all that apply. (It suffices to visually identify critical path.) Path A-B-D-F Path A-B-E-F Path A-C-E-F Question 10 (Continue with the preceding question.) Please manually crash the project by 1 day at minimum extra cost. The activity that should be crashed is/are: (Please select all that apply.) A B C D E F (Answer this question independent of the preceding question.) With normal duration of all activities, we find that the project's duration is 31 days. Please formulate a Linear Program that minimizes the costs for crashing the project by at least four days. Please use the following decision variables: Xi : the Earliest Start date (ES) of activity i for i=A,B,C,D,E,F; Yi : \# days to be shortened for activity i. Please upload your result as a file. (Continue with the preceding question.) Suppose that in addition to the constraints in the preceding question, we have to enforce a new constraint: "Earliest possible date to start activity C is two days after the completion of activity B." Which of the following represents this new constraint correctly? (Note: XC, YC, XB, and YB below are the plain form of XC,YC,XB, and YB.) XCXB+(6YB) XCXB+(6YB)+1 XCXB+(6YB)+2 XBXC+(7YC) XBXC+(7YC)+1 XBXC+(7YC)+2 Problem Statement: Project Crashing Consider a project with 6 activities, A through H. The following table contains the normal duration (in days), normal cost, crash duration (in days) and crash cost of all activities, as well as the cost slope (positive part) of all activities. The project's AON network diagram is shown below with the normal durations of the activities filled in the boxes. You are invited to crash this project based on the data given in the table and network diagram above. Answer the following questions. Before crashing the project, please identify all critical path(s). Please select all that apply. (It suffices to visually identify critical path.) Path A-B-D-F Path A-B-E-F Path A-C-E-F Question 10 (Continue with the preceding question.) Please manually crash the project by 1 day at minimum extra cost. The activity that should be crashed is/are: (Please select all that apply.) A B C D E F (Answer this question independent of the preceding question.) With normal duration of all activities, we find that the project's duration is 31 days. Please formulate a Linear Program that minimizes the costs for crashing the project by at least four days. Please use the following decision variables: Xi : the Earliest Start date (ES) of activity i for i=A,B,C,D,E,F; Yi : \# days to be shortened for activity i. Please upload your result as a file. (Continue with the preceding question.) Suppose that in addition to the constraints in the preceding question, we have to enforce a new constraint: "Earliest possible date to start activity C is two days after the completion of activity B." Which of the following represents this new constraint correctly? (Note: XC, YC, XB, and YB below are the plain form of XC,YC,XB, and YB.) XCXB+(6YB) XCXB+(6YB)+1 XCXB+(6YB)+2 XBXC+(7YC) XBXC+(7YC)+1 XBXC+(7YC)+2