Consider a Project That Has Been Modeled as Follows

Consider a project that has been modeled as follows:

a.Draw the PERT/CPM network for this project and determine project's expected completion time and its critical path.
b.Can activities E and G be performed simultaneously without delaying the minimum project completion time?
c.Can one person perform A,G,and I without delaying the project?
d.By how much can activities G and L be delayed without delaying the entire project?
e.How much would the project be delayed if activity G was delayed by 7 hours and activity L was delayed by 4 hours? Explain.