15th to the 17th centuries were the Age of Exploration
After the split from the supercontinent, the individual continents underwent a number of changes of their shoreline. For example, the constant flow of water "smoothed" the surface, which meant that in some parts the land decreased (was washed away by the currents) and in other parts the land increased with the accumulation of the material that the currents brought.
This changed the shape of the continents in a way that they no longer "fit" together perfectly.
Answer:
Congress reviews a judicial decision and overturns the Supreme Court
Explanation:
It was Called the frontier because some or most of the areas in America that where settled by ranchers hadn't been explored or discovered yet.
