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.
Time Series Graphs. Data is displayed in a time series graph at various time-points. This is another type of graph used for specific kinds of data that come in pairs. The vertical axis is for data values while the horizontal axis shows time. This kind of graph can be used for showing trends passing through a time period.