Answer:
2009 data set is most homogeneous
Explanation:
As per coefficient of variation, which is around 5% for the year 2009 and around 20% for the year 2010 we can state that the data set for the year 2009 is most homogeneous
Homogeneous means similar, it can be observed on the graph as well that the data for the year 2009 is less variant
Hope it answers your question.