They can help strengthen a point as long as the question is then enforced. They help to convince the listener since usually even thought it's not said we usually think yes in our head after hearing a rhetorical question.
#1-“‘An’ have rabbits. Go on, George! Tell about what we’re gonna have in the garden and about the rabbits in the cages…’”
#2 This quote can be found on page 14
#3 The symbol is the rabbits. The rabbits represent Lennies' naïve side.
#4 It is an example of Lennies dreams while in the Great Depression.
I dont understand what you are asking for in the question, considering there is no paragraph or specific details