Based on the clue 'at 55 mpg you could get from la to vegas on a bout...', what is the answer?

What is associated with: at 5200 square miles its the largest lake in venezuela in all of south america? What is associated with: at 5305 feet mount ossa is the highest point on this devilish australian island? Based on the clue 'at 54 weighing 100 lbs he was our shortest presid...', what is the answer? What is associated with: at 541 am on may 1 1898 dewey told this captain of the olympia you may fire when you are ready? Based on the clue 'at 563 carats the star of india a blue one of thes...', what is the answer? Based on the clue 'at 57th you can gaze in this stores windows as hol...', what is the answer? What is referred to by 'at 58 fleming'? Based on the clue 'at 58 in length the gallinipper is one of the larg...', what is the answer?