Answer:
1- b. False
2- b. use personal pronouns like "we" or "us."
Explanation:
So for first Question, the correct answer is b, as initial audience disposition does not have any impact upon the agreement of audience with the speaker's talk. Audience disposition or a knowledge about that topic , does not have anything to do with the agreement or disagreement. It is Speakers way of presenting his ideas, that can affect the agreement of audience.
Speaker can establish the common grounds by using pronouns like we, us. In this way audience will be more comfortable and will feel things related to themselves. Thus all the successful speakers, use such type of words to bring audience into their comfortable zones, it has very good impact on speech.