Answer:
The word that the author used to indicate how Eliza was feeling is scowled.
Step-by-step explanation:
To scowl is to have an angry or bad tempered expression.
Eliza was said to have scowled and waved the towel at the flies buzzing above the bowl. This shows that she was angry with the interference of the flies as they were a nuisance to her.
So, the word used to show how Eliza was feeling is scowled.