Ahigh school student named david merrell did a study of how music affects the ability of rats to run a maze. he trained 71 rats to run a maze. next he divided the rats into three groups. for the next month, one group listened all day to heavy metal music by the group anthrax. a second group listened all day to mozart. the third group never heard music. this group is the control group. the rats ran the same maze three times a week for a month. the response variable is the time in seconds to complete the maze. by the end of the month the anthrax group was much slower at running the maze. the mozart group was much faster. the dotplots below show average run times for the first and last week of the experiment. each dot represents one rat. the value is the rat’s average run time for the week. (each rat ran the maze 3 times each week.) the blue line is the mean run time for each treatment group. merrell claims that he randomly assigned rats to treatment groups. does the data support his claim? why or why not?