It's a claim which is capable of argument, not an undisputed fact; and so merits a question mark. Given that ...
a) It's quite possible to frame questions in impeccable grammar and English to which there are no sensible answers. i.e. What colour is Tuesday ?
b) It's quite possible to frame intelligible questions which would get a responsem despite using unconventional grammar, i.e. " This Regent Street ?"
And while you're at it, look up Skitt's Law.
michael adams
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