What kind of graph would you use to see the fractions of different gases in the atmosphere?

A pie chart would be an effective way to represent the fractions of different gases in the atmosphere, as it visually displays the parts of a whole. Each slice of the pie can represent the percentage composition of each gas, allowing for easy comparison of their relative abundances. Alternatively, a stacked bar graph could also be used to show the same information, particularly if you want to emphasize changes over time or across different locations.