Even though you can look at the critical path by examining the Total Slack values for your tasks , it's often easier to view and think about the critical path in a graphical way. The Tracking Gantt is a built-in view that shows the critical path colored in red.
Using the Tracking Gantt to View the Critical Path
Click View, Tracking Gantt on the menu bar. 
Observe the critical path shown in red. 
