If the scale is 0 to 20 by twos, then it includes bar numbers 0, 2, 4, 6, 8, 10, 12, 14, 16, 18 and 20.
Since the bar graph shows that sports books received 9 votes, then the bar should end in the middle between 8 and 10 (because 9-8=1 and 10-9=1).
Answer: in the middle between 8 and 10