A Histogram is a bar chart showing the frequency of an outcome. They can reflect the voice of the process & will certainly be on your exam.
The Central Limit Theorem states that the distribution of the sample means approaches normal regardless of the shape of the parent population.
A check Sheet is a data collection tool that usually identifies where and how often problems appear in a product or service.
A Pareto Diagram is a bar chart that re-orders the categories so they are rank-ordered from the largest total occurrences to the smallest.
How to determine baseline project sigma is one of the key aspects of the Measure phase. It is part of the data collection plan.