An individual who is actively involved in government activities could be described as a person who is politically active. They could also be a member of the government or the political elites.
The rate of natural increase refers to the difference between the number of live births and the number of deaths occurring in a year, divided by the mid-year population of that year, multiplied by a factor (usually 1,000). It is equal to the difference between the crude birth rate and the crude death rate.
Yes it is divded into 12 main cultures