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Recently, I've found myself writing sentences which are statements, but which conclude with a question, either in parentheses or as a quotation, and being unable to decide quite how to punctuate.
She said, "Are you coming home?" -- versus -- She said, "Are you coming home"?
He looks unhappy (but isn't he rich?) -- versus -- He looks unhappy (but isn't he rich?).
Also, is this affected by whether on not one is using British Punctuation (cf. the Oxford Comma) or American Punctuation?