ABCD is a quadrilateral in which AB || DC and AD = BC (see figure). Show that:

(i) ∠A = ∠B and

(ii) ∠C = ∠D

[Hint: Extend AB and draw a line through C parallel to DA intersecting AB produced at E]

How have intensive industrialization and urbanization posed a great pressure on existing fresh water resources in India? Explain.

मीरा ने किसे अपना पति माना है ?

The marks obtained by 40 students of a class in examination are given below:

3, 20, 13, 1, 21, 13, 3, 23, 16, 13, 18, 12, 5, 12, 5, 24, 9, 2, 7, 18, 2, 3, 10, 12, 7, 18, 2, 5, 7, 10, 16, 8, 16, 17, 8, 23, 24, 6, 23, 15.

Present the data in the form of a frequency distribution using equal class size, one such class being 10-15 (15 not included).

Which of the following is an example of Emulsion?

(a) mayonnaise 

(b) shaving cream 

(c) fumes 

(d) paint