This question is incomplete. Her speech was to convince the public of America's strength.
She said, 'We take off our hats to the farmers who have faced an unprecedented task of feeding not only a great Nation but a great part of the world'.
It stresses a positive idea and invigorates the audience. Roosevelt convinces the public to support an idea to encourage the public to unite to motivate the public to take action. It encourages the public to act with a united front.
