A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first sentence because it introduces John F. Kennedy and gives important information about him. It does not need another sentence to understand it. It is a general statement about Kennedy's victory. Why other lines are not chosen? The other paragraphs are not chosen because they do not stand alone. For example, Paragraph 2 starts with 'In his first inaugural address,' which needs context. Paragraph 3 starts with 'On television,' which also needs more information. Paragraph 4 starts with 'In the campaign,' which is not clear without prior context.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it wraps up the ideas about Kennedy's campaign. It gives a final thought about his vision for the future. It summarizes his goals and ideas.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects with Paragraph 1 because it continues to talk about John F. Kennedy. It uses a logical order as it moves from his victory to his inaugural address.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects with Paragraph 2 because it shows how Kennedy was seen during debates. It follows a logical order, moving from his speech to his performance on television.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects with Paragraph 3 because it talks about Kennedy's campaign. It continues the topic of Kennedy's actions and ideas, showing a logical order.