Answer:
Migration is a form of geographic or spatial movement involving a change of usual residence between clearly defined geographical unit.Human beings,like other creatures,leave the place in which they dwell,in order to obtain some goals. The reasons they move from one place to another are geographical, social,political and economic as well.such movement is called migration.
Step-by-step explanation:
Migration is measured by following measures:
1=In-migration rate
2=Out-migration rate
3=Net migration rate
4=Gross migration rate
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