Logos appeal to the audience's reasoning. For example, I build up a logical argument by presenting facts that I know everyone will agree with, or reason with.
Ethos appeal to the speaker's status, which may make the audience trust them more. For example, I am speaking on a podium, and I say "Because [my profession], this product is [positive adjective] to be used."
Pathos appeal completely to emotions, making the audience feel a certain way. For instance, someone tries to convince me to give them dog treats because they have an adorable puppy.
B. There is no single topic sentence. It starts with an idea and just keeps flowing. A topic sentence will introduce the point in why the are talking about earth's plates.
