The table below shows the population distribution and land area of five states of a country B in the year 2010. Use the data to answer the following questio...

(a) Calculations. The data for the five states are shown below.

State	Population (millions)	Land area (km\(^2\))
1	3.2	140,000
2	5.4	98,000
3	7.4	35,000
4	6.5	120,000
5	4.2	86,000

(i) Total population.

\[3.2+5.4+7.4+6.5+4.2=26.7\ \text{million}=26{,}700{,}000\ \text{persons}.\]

(ii) Total land area.

\[140{,}000+98{,}000+35{,}000+120{,}000+86{,}000=479{,}000\ \text{km}^2.\]

(iii) Population density of country B.

\[\text{Density}=\frac{\text{Total population}}{\text{Total land area}}=\frac{26{,}700{,}000}{479{,}000}=55.74\approx\mathbf{56\ \text{persons per km}^2}.\]

(b) Four factors that influence the distribution of world human population

1. Climate: regions with moderate temperature and reliable rainfall are densely settled, while very hot deserts and very cold or wet areas are sparsely peopled.
2. Relief: flat lowlands and plains carry dense populations, whereas rugged highlands and steep mountains are thinly settled.
3. Soil and agriculture: fertile soils that support good farming attract dense settlement; infertile land repels it.
4. Job opportunities and industrialisation: areas with industry, commerce, mineral deposits and good transport attract people in search of work, giving high densities.

(c) Three factors that cause increase in world human population

1. Increase in birth rate, encouraged by early marriage and preference for large families.
2. Decrease in death rate through improved medical facilities, hygiene and sanitation.
3. Adequate food supply and improved standard of living from better agriculture.