Given an trivia question precisely answer the question with a word/phrase/name. External resources such as Wikipedia could be used to obtain the facts.

In the Shakespeare play 'Macbeth', which character carries Macbeth's head on stage?
macduff

Which American playwright wrote The Iceman Cometh and Long Day's Journey Into Night?
eugene o'neill

What is the name for the negative pressure generator invented by Robert Henderson and used extensively by Phillip Drinker and Louis Agassiz Shaw?

iron lung