It doesn't allow me to crop the questions with the data below. So, I will put it right here: A) indicate the independent and dependent variables for each study (if applicable) B) what type of research design was used (if applicable) C) which t-test was used to analyze the data?

The question: a sociologist was interested in the decline of racial discrimination in a particular geographical region from the 1960s to present. The number discrimination cases in this area were counted in 1960, and the average number of discrimination cases back then was approximately 110. A random sample of cities was obtained this month in the same area, and the average number of discrimination cases was approximately 57. Based on this study, is there enough evidence to suggest that discrimination has significantly declined since the 1960s?

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