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.
Which Graph to Use. Now decide which type of graph would be best to show the relationship between the cost of fighting emergency fires and the year in which the fires occurred. The four types of graphs, you should recall, are bar graph, pie chart, line graph and scatter plot. You decide - remember what each of the four types of graphs are best at showing: Bar graph - compares items and relationships - a groups of things you want to compare.