A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first because it introduces the main topic. It tells us about Eric the Red and his landing in Greenland. This is a clear starting point for the story. It does not use any words that need prior knowledge, so it stands alone. Why other lines are not chosen? The other paragraphs are not chosen because they do not meet the rules for being independent. For example, Paragraph 2 starts with 'He', which is a pronoun and needs context. Paragraph 3 starts with 'The settlement', which uses 'the' and assumes prior knowledge. Paragraph 4 starts with 'The island', which also uses 'the' and needs context.

Concluding sentence: Why this is the last line? This paragraph is the last because it wraps up the story. It gives the final information about the island and its change in control. It shows the end of the historical timeline.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects to Paragraph 1 because it continues the story of Eric the Red. It uses the connector 'He' to show that it is about Eric. This shows a logical order of events.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 follows Paragraph 2 because it talks about the result of Eric's return. It shows the logical order of how the colony was formed and how long it lasted.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects to Paragraph 3 because it talks about what happened after the settlement ended. It shows a logical order of events from the settlement to the recolonisation.