Most likely due to the movement of plate tectonics. They are plates of earth under the ocean that move occasionally, over the years this is probably what happened.

The greater density of old lithosphere relative to the underlying asthenosphere allows it to sink into the deep mantle at subduction zones, providing most of the driving force for plate movement. The weakness of the asthenosphere allows the tectonic plates to move easily towards a subduction zone.

Explanation:

the answer is a) james madison.

answer is 1935

because gandhi led a march the sea in 1930 and 5 years later he did it again