Can a presenter really change his/her image from presentation to presentation? If so, how? Is it ethical? Try to think of an example in which this might happen or has happened. What are/were the results?
I would contend that a presenter could indeed change his or her image to a degree. The methods for doing so are quite numerous. A speaker can alter their literal tone, their choice of clothing (which sends many psychological messages), the environment where they shall give the presentation, the elements of the presentation, and their technique of interaction with the audience.
Is it lying? The ethics associated with doing so ...