California seems more like SW than W to me. Qn 15 seems pretty inane since there must be dozens of possible meanings for "BTS". I've no idea which one you were referring to but the one of which I was a member, the British Trauma Society, doesn't come from any of the countries suggested. I am reminded of a wise teacher who said that if you use an abbreviation that I don't understand then it is not I who is the foolish one. Finally you need to correct the spelling of Caracas.