How did Camus bring an optimism to existentialism?
Camus established that our situation as a human being can be optimistic if we realize that the world is absurd and we rebel within that experience to create our own meaning.
What key signature or key signatures has one sharp and what note gets the sharp?
The key of G Major and it's relative minor key E minor have one sharp, and the note that gets the sharp is F, so it is F#.
What part of speech is the work "marching" in the sentence "Jill joined a marching band."
"Marching" is a present participle.