1. What is the difference between a column graph and a bar graph
They are both the same.
A histogram is used for continuous data such as measurments and the bars are joined together.
2. Can a pie graph be used for all types of data?
No. Pie graphs or charts are most suitable to data where proportions or percentages of a total amount are available .
3. How can the pictures in pictographs show numbers?
Each picture represents a certain number of items.