2.4

In the instance of instructor shown in Figure 2.1, no two instructors have the same name. From this, can we conclude that name can be used as a superkey (or primary key) of instructor?

No. For this possible instance of the instructor table the names are unique, but in general this may not always be the case (unless the university has a rule that two instructors cannot have the same name, which is a rather unlikely scenario :) ).