Answer:
growth rate will be 4.5 %
So option A is correct option
Explanation:
We have given immigration = 50
Emigration = 20
Birth rate = 25
Death rate = 10
Each per 1000 people
We have to find the percentage growth rate of this country
Percentage growth is given by immigration - emigration + birth rate - death rate
So percentage growth rate = 
%
So growth rate will be 4.5 %
So option A is correct option
The least developed nations tend to have lower levels of industrial activity, resulting in lower levels of environmental damage. The most developed countries have found ways of improving technology and energy efficiency to reduce their environmental impact while retaining high levels of production
Explanation:
Olivine -
It is the primary component of the upper layer of mantle , Olivine is one of the common mineral present on the subsurface of Earth .
The structure of olivine is neosilicate . The general formula is
( Mg²⁺ , Fe²⁺ )₂SiO₄
It has an independent unit of SiO₄ , which is independent , having a tetrahedral structure .
