Tea Tree Oil is used commercially in many products including shampoos, body lotions and toiletries, but there is no legislation requiring manufacturers to state the concentration of tea tree oil in these products.
Line Graphs. One of the most common graphs you will encounter is a line graph. Line graphs simply use a line to connect the data points that you plot. They are most useful for showing trends, and for identifying whether two variables relate to (or correlate with) one another.
Here are some popular types of graphs and charts: 1  Some of the basic graphs used for categorical data include pie charts and bar graphs, which break down how many responses were given for each group of certain variables, such as gender or which applications are used on teensâ cellphones. An example of a bar graph.