What is Aristotle's term for a speaker's credibility?

Which of the following is a guideline for using presentational aids during the speech?

a. Show or play presentational aids at the beginning of the speech. b. Position presentational aids and equipment before beginning your speech. c. Stand behind presentational aids when presenting them. d. Talk about your visual aid before showing it.

Describe the types of supporting material that you can use in your presentations. 

What will be an ideal response?