What is the best meaning of the word cacophony as it is used in the sentence below?

Despite the cacophony, the student tried to study.

What is the best meaning of the word punctilious as it is used in the sentence below?

Our ELA teacher is very punctilious about grammar.

What is the best meaning of the word ebullient as it is used in the sentence below?

The Broadway show was filled with ebullient performers, and the audience gave a standing ovation at the end of the performance.

What is the best meaning of the word loquacious as it is used in the sentence below?

She put her headphones on, fearful of being seated next to a loquacious passenger.