Fill up the blanks by choosing the right option.

(i) Public conveyances like buses and railways are …………… (necessities/luxuries).

(ii) Many sets of garments per member in a family is …………… (a necessity/fashion).

(iii) Petroleum is a resource of the same category as that of …………… (copper/ground water).

Give the technical terms for the following :

(i) Statistical study of human population.

(ii) Number of deaths per 1000 people per year.

(iii) Number of individuals per sq. km. at any given time.

(iv) Difference between birth rate and death rate.

List any five major disadvantages of having large families.

What are the age restrictions for marriage for boys and girls respectively in India ?