How can the stacking bar plot show n observations in each group in an easily understandable way?

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One way to make the stacking bar plot easily understandable is by including a visual representation of the total number of observations in each group as well as the proportion of each observation type within the group. This can be achieved by color-coding each observation type and labeling the bars with the total count and percentage of each type. Additionally, including a legend explaining the colors and their corresponding observation types can further enhance the clarity of the plot. Finally, providing clear and concise labels for the x and y axis can help the viewer easily interpret the data being presented.