Students in California are required to pass an exit exam in order to graduate from high school. The pass rate for San Luis Obispo High School has been rising, as have the rates for San Luis Obispo County and the state of Cali fornia (San Luis Obispo Tribune, August 17, 2004). The percentage of students who passed the test was as follows:

Year District Pass Rate 2002 San Luis Obispo High School 66%
2003 72%
2004 93%
2002 San Luis Obispo County 62%
2003 57%
2004 85%
2002 State of California 32%
2003 43%
2004 74%

a. Construct a comparative bar chart that allows the change in the pass rate for each group to be compared.

b. Is the change the same for each group? Comment on any difference observed.