If Edna wants her speech to persuade as much of the audience as possible, what should she add to her speech

Edna should add a reliable source to help persuade the audience as much as possible. She can also include quotes from that source to help prove her point, that an improved lunch will help the students do better in class.

Explanation:

This is just what I would write, I'm not sure if this is what you are looking for but I hope it helps.  

for this, you need to remember something significant in your own life, for example, if you were bullied when you were younger, you can mention your memories on this and touch on how such treatment can harm other kids your age either physically or mentally. (racism, car crashes, a parent in the hospital are all very good subjects, think hard on it! )

hope i ! : )