When Tia walks into the store, how should Carla greet her?

HI how may I help you today?

Explanation:

Or you could do HI, wlecome to (name of the store) how can I assist you today?

The central idea/thesis in an informative speech should include all the guidelines mentioned except option 2) “At least two different kinds of support materials.” When delivering a speech you don’t need to include several support material such as videos, power point presentations and other visual or audio aids.

The important point when giving a speech is to make sure that your audience understands or is related to the topic you are about to talk about. Besides, it is very important that you have credibility as orator either because you know about the topic or because your audience believes you are knowledgeable to talk about a certain issue.  

Also, your central idea sentence should provide the audience hints and a forecast of the main ideas that will be developed during the speech.  

And finally, it is essential that you apply certain attention techniques so that your audience gets involved in the speech. You can call the audience’s attention by bringing examples or telling anecdotes that illustrate your speech.