3- The project implementation phase embraces the period from the decision to invest to the start of commercial production. It includes a number of activities, including negotiation and contracting, project design, construction and start up. the following table shows a realistic schedule for the various stages/activities of the investment phase of project implementation. Activity Start A B C D E F G H J K Must Precede A,F B C,D E End End G,H I,J J End K End Duration (day) 15 5 8 8 9 7 14 6 a) Draw activity network for the project implementation phase? b) What are the critical activities of the final schedule? c) Identify the critical path?