The information that are in a climate graph are temperature and rainfall.
Yes always.
a valid conclusion based on the information in the graph is that
A pie chart is used to represent parts of a whole.
I believe trends in data should be presented in a graph.
by graph
monthly temperatures :D
Histograms are generally used when quantitative information is presented for groups (classes) of different sizes (class widths).
There are very many ways in which information can be presented in graphic form. On of my personal favourite graphs is Minard's graph of Napoleons's army's invasion of Russia: http://en.wikipedia.org/wiki/French_invasion_of_Russia#Weather_as_a_factor The interpretation of the graph depends on what information is being plotted, with what axes and also what other information is plotted with it.
the line graph is the temperature!
No it could not
With a graph you get an almost instant visual image of the data presented.
They are ways in which data can be presented visually.