What is likely to occur at a plate boundary where oceanic crust collides with continental crust?

Which objects allow humans to access groundwater? check all that apply.

How did the korean war impact the elections of 1952?

This is a 2017 topographic map of puerto rico in the united states, and i'm sorry that people there have suffered such a disaster. i want to ask, what do the yellow dots and areas represent on this graph? and the blue area and the little blue circle, and the little blue sign that looks like a signal tower, what do they stand for?