6. [20 points] A project for upgrading a point-of-sale system at a local business has following Precedence relationships and activity times. The tasks and predecessor relationships are shown as follows: a. Draw the network for this project. (You can draw in paper, scan it and insert to your assignment or use computer to draw the diagram. Please see Content Student Resources Study Aids Assignment Resources if you need technical guidance). b. Identify which activities can be done concurrently. (There are several groups of activities which can be done concurrently)