Which type of graph uses wedges to show the amount of data points in a category?

A Pie chart graph.

Explanation:

A pie chart graph is defined as the circular graph which shows the contribution of different categories with respect to overall data.

A wedge of the circle represent the contribution of each category, such that these graphs are resembles a pie that has been cut into different slices. Every one percent is contributed to the 3.6° of total area.

Therefore, by the above discussion it can be says that pie chart graph uses wedges which shows the data points amount in a category.

e/c, where e is its total energy