Answer:
It affects them by the food and materials
Explanation:
I think the answer is nostalgic. Based from the excerpt, Richie missed
the old time when he was younger. He felt melancholy as he tried to
describe himself from his younger years. Rich felt that he had changed a
lot since then. He felt that he is more energetic when he was younger
compared to his present self.
This part of the thesis would be considered the topic, more specifically it would be considered the <em>introduction of the topic to study</em> since the thesis revolves around, I assume, Isaac Newton and you are offering a brief 'summary' of his life and accomplishments.
However if the reason to mention Sir Isaac Newton is to support an idea or a statement this could be considered a subtopic. It is subjective and directly related to the field of study you're doing the thesis for.
Hope this helps!