A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first line because it introduces the main topic. It talks about Wal-Mart's core shoppers and their money problems due to rising gasoline prices. This is a broad overview of the situation. It does not refer to any previous information, so it stands alone. Why other lines are not chosen? The other paragraphs are not chosen because they do not meet the criteria for being independent. For example, Paragraph 2 starts with a quote and refers back to the CEO, which means it needs context. Paragraph 3 talks about shoppers but does not introduce the main topic. Paragraph 4 is a quote that also needs context from earlier sentences.

Concluding sentence: Why this is the last line? This paragraph is the last line because it wraps up the discussion. It summarizes the main point about shoppers running out of money. It reflects the overall theme of the text, which is about the financial pressure on Wal-Mart shoppers.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects to Paragraph 1 because it uses a quote from CEO Mike Duke. This shows a direct link between the two paragraphs. The quote explains more about the pressure on consumers, which follows the concern mentioned in Paragraph 1. This is a logical order.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects to Paragraph 2 because it explains who the core consumers are. It gives more details about Wal-Mart shoppers and their shopping habits. This is a broader to specific strategy, where the second paragraph introduces the problem, and the third paragraph gives specific information about the shoppers.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects to Paragraph 3 because it summarizes the situation of the shoppers. It shows the result of their shopping habits and how they are running out of money. This is a cause and effect relationship, where the shopping habits lead to the problem of running out of money.