A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first sentence because it introduces the main topic of street performers. It gives a broad overview of what the text will discuss. It does not use any specific details or references to other sentences. Why other lines are not chosen? Paragraph 2 starts with 'These', which is a pronoun that refers back to street performers, so it cannot be first. Paragraph 3 starts with 'According to', which suggests it needs more context. Paragraph 4 starts with 'The data', which also needs prior information. Paragraph 5 starts with 'Overall', which indicates it is summarizing and cannot be first.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it summarizes the main ideas of the text. It uses the word 'Overall', which shows it is concluding the discussion about street performers.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects to Paragraph 1 because it gives more details about street performers. This follows the Broader to Specific Strategy, where the first sentence is general and the second sentence provides specific examples.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects to Paragraph 2 because it gives factual information about street performers. This follows the Logical Order, where the second sentence builds on the details given in the first.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects to Paragraph 3 because it explains the importance of street performers in the economy. This follows the Cause and Effect Relationship, where the revenue generated leads to their significance.
• Pair 4 (Paragraph 4 → Paragraph 5): Paragraph 5 connects to Paragraph 4 because it summarizes the importance of street performers. This follows the Summary Style, where the last sentence wraps up the main points discussed.