Section 1:
Part A: What effect does the word head have on the meaning of this passage?
The use of the word "head" demonstrates how intelligent he was. He was the head of his class, which means he had the best grades of everyone in his entire class.
Part B: How does the choice of the word head contribute to the passage’s tone?
The use of the word head contributes a sense of pride to the passage's tone. He didn't mention that he was at the head of his class because he felt entitled to something better, but rather because he had pride in his accomplishments.
Section 2:
How does the word exquisite contribute to this passage?
Exquisite is used to create emphasis. The author uses it to describe his pleasure and wanted to convey he found it very pleasurable.