Answer:
The Mexican army attacked them. The main cause of the war was the westward expansion of the United States. All through the 19th century Americans believed it was their right to expand westward. At the time they believed they could conquer the people already living on the land and take it for the United States.
Explanation:
The three major rivers of india are orginated in himalaya mountains
The County unit system. See the link below that will take you to that.
