Finding the area of figure which is combinations of triangles and quadrilaterals

In the adjoining figure ABCD, PQRS and WXYZ are three squares. Find number of triangles and quadrilaterals in the figure :

Find the area of given quadrilateral."

Find the area of the Quadrilateral

find the areas of the following quadrilaterals.

If the diagonals AC,BD of a quadrilateral ABCD, intersect at O, and separate the quadrilateral into four triangles of equal area, show that quadrilateral ABCD is a parallelogram.