Professor Jones asks Professor Brown to cover class for her while she is out of town presenting a paper at a conference. They are good friends and work together effectively on several committees. Professor Brown not only covers the class, but develops a special lecture and exercise for the students. Professor Jones is using her power and Professor Brown is .

Professor Jones is using her REFERENT power and Professor Brown is COMMITTED.

Explanation: Referent means someone who can actual stand for you in this case Professor brown is going to stand for Professor Jones in his absentia.

Commited refers to being completed devoted to the task at hand and that we see by Professor Brown going an extra mile in delivering the task he has been given by Professor Jones."Professor Brown not only covers the class, but develops a special lecture and exercise for the students"

the primary theme of ha jin's “a decade” would be the need to revisit one's past to determine a path for the future. “a decade” is one of the twelve brief stories of ha jin's under the red flag, which takes place during the cultural revolution of china.