A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first sentence because it introduces the main topic of the text. It gives a broad overview of what the Ecological Footprint is about. It does not use any specific details or references to other ideas. Why other lines are not chosen? Paragraph 2 starts with "On the demand side," which means it needs context from another sentence. Paragraph 3 starts with "The Ecological Footprint tracks," which also needs prior information. Paragraph 4 starts with "On the supply side," needing context. Paragraph 5 starts with "Both the Ecological Footprint and biocapacity," which assumes knowledge of previous ideas.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it wraps up the discussion. It gives a final point about how both concepts are measured. This shows a summary style that brings together the earlier points.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects to Paragraph 1 because it explains the demand side of the Ecological Footprint. This is a logical order because it follows the introduction of the topic with specific details about what the Ecological Footprint measures.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 follows Paragraph 2 because it gives specific examples of the categories measured by the Ecological Footprint. This shows a broader to specific strategy, where the general idea of demand is followed by specific types of land.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects to Paragraph 3 because it shifts from the demand side to the supply side. This shows a logical order where the text moves from what is needed to what is available.
• Pair 4 (Paragraph 4 → Paragraph 5): Paragraph 5 follows Paragraph 4 because it summarizes the relationship between the Ecological Footprint and biocapacity. This shows a logical order where the conclusion ties together the ideas of supply and demand.