How many pairs of parallel lines are there in the figure?
A closed figure can be formed if there are more than one pair of intersecting lines. How many intersecting lines are there in a triangle? ___
In the adjoining figure, ABCD is a quadrilateral. (i) How many pairs of adjacent sides are there? Name them. (ii) How many pairs of opposite sides are there? Name them. (iii) How many pairs of adjacent angles are there? Name them. (iv) How many pairs of opposite angles are there? Name them. (v) How many diagonals are there? Name them.