Which formula is used to calculate population density?

The geometric representation of age structure is a characteristic of:

Bell-shaped age pyramid indicates that

Consider the birth rate and death rate per year in a given population.
Total population after $5$ years $\rightarrow 100$
Number of individuals dying per year $\rightarrow 10$
Number of individuals born per year $\rightarrow 20$

The geometric representation of age structure is known as:

The percentage of the population of India living in Madhya Pradesh $(M.P.)$ at present is approximately: (in $\%$)