On the morning of his classroom speech, jonah felt that he needed more visual interest in the speech. on his way to class, he bought poster board and a marker and wrote down his main points for the audience to see. did robert follow the guidelines for visual aids presented in your textbook?

No. Robert should have prepared the chart ahead of time and rehearsed with it
If a chart is used during a prensentation now it became integrated with the main content of the presentation.
So, in order to avoid potential confusion or mismatched, robert Should've prepare all the needed data at home and conducted some practices on how to use it precisely in front of the audience.