Copernicus should be the topic, and the central idea should be how he came up with the heliocentric theory. I hope I helped, please tell me if I am incorrect or if you need more help!
If you write one sentence describing the original paragraph's hook, and then a second sentence describing any supporting evidence in the paragraph, and then a third sentence describing the topic sentence, you will have written your critique.
Answer: Increases.
Explanation: When the amount of surface area relative to volume increases, the rate of weathering increases.