What is referred to by '2 4 10 16'?

Based on the clue 'this is an extension of the initials us', what is the answer? What is referred to by 'tobago'? Which performer is associated with 'wings'? What is the first number? What is referred to by '273 celsius'? What is associated with: 27315 degrees c? What is associated with: 27316 degrees centigrade? Based on the clue '40 is the only reading on these 2 temperature scal...', what is the answer?