(i) The monthly rainfall in a year can be best represented by a bar diagram as only one
variable i.e., monthly rainfall is to be presented diagrammatically. The rainfall is plotted on Y-axis in the corresponding month that is plotted on the X-axis.
(ii) Composition of the population of Delhi by religion can be represented by a component bar diagram. A component bar diagram shows the bar and its sub-divisions into two or more components. Thus, the total population can be sub-divided in terms of religion and presented through a component bar diagram.
(iii) Different components of cost in a factory can most effectively be depicted through a pie chart. The circle represents the total cost and various components of cost, are shown by different portions of the circle drawn according to percentage of total cost each component covers.