In the class, the professor explained Chain-of-Thought (CoT), which is a state-of-the-art reasoning model, and he also emphasized the importance of writing a clear proof with detailed statements. 

As a step of learning, you will need to write a table on paper for a detailed proof and CoT. The table shall have three columns:

1. Step (copy the numbers in the proof on Page 3 of "Chapter 1 - Forms and Techniques for Proofs")
2. Statement (copy the statement in the proof on Page 3 of "Chapter 1 - Forms and Techniques for Proofs")
3. CoT: choose 5 most important steps as your CoT for this proof, and specify them by using 1, 2, 3, 4, 5 in this column.

For this problem, you need to scan (or take a photo of) your table, generate a jpg file, and then upload it.