Nice quiz and thank you for it, but the Chrysler Building is on 42nd Street and Lexington Avenue - well inland, and south of the mark on the map. I tried every name for the United Nations (plaza, general assembly, secretariat, complex) which obviously did not work, but that IS where the U.N. is located.
This is not a New York City geography quiz, its a Manhattan geography quiz. Calling this a New York City quiz would be like calling a quiz about English Geography a United Kingdom Geography quiz.