Based on the clue 'at the spanish riding school in vienna you can see...', what is the answer?

Based on the clue 'at the site for this government department you can...', what is the answer? Based on the clue 'at the smithsonian you can see this plane in which...', what is the answer? Based on the clue 'at the smithsonians national portrait gallery you ...', what is the answer? Based on the clue 'at the sorbonne she studied philosophy met sartre...', what is the answer? What is associated with: at the st louis exposition of 1904 this apache leader signed sold autographs? Based on the clue 'at the start of a chess match you have 8 of these ...', what is the answer? Based on the clue 'at the start of a game of checkers each player has...', what is the answer? Based on the clue 'at the start of a game of pool there are this many...', what is the answer?