The following dot plot represents student scores on both the Unit 1 and Unit 2 math tests. Scores are in whole number increments.

Part 1: Looking at the data plots, which test do you think the students scored better on? Do you think one of the tests has more variation than the other or is the variation about the same for both tests? Use complete sentences in your answer and explain your reasoning.
Part 2: Calculate the mean (rounded to the nearest whole number) and mean absolute deviation for the Unit 1 test.
Part 3: Do your results from part B prove or disprove your hypotheses from part A? Use complete sentences in your answer and explain your reasoning.