Graffiti ~ Graffiti is writing or drawing made on a wall or other surface, usually without permission, and within public view. It ranges from simple written words to elaborate wall paintings, and has existed since ancient times, with examples dating back to ancient Egypt, ancient Greece, and the Roman Empire. Most people see graffiti as a form of vandalism and an eyesore, and its presence increases people's fears that other crime is common in the area. Janae is a data scientist who works for New York City, which is divided into five boroughs (incorporated towns). Police records in each borough track the reports of graffiti in the borough and note the status of the report as either "Open" or "Closed". Janae wonders if there is a relationship between the borough and the status of a report. The following table presents a sample of 845 reports of graffiti in each of New York's five boroughs (incorporated towns) over a one-year period. BoroughOpen ReportsClosed ReportsTotal Bronx5496150 Brooklyn75160235 Manhattan48200248 Queens87111198 Staten Island7714 Total271574845 1. Which statistical test should Janae use to answer her research question? A. 2 goodness of fit test B. t test for sample mean C. Z test for difference of two population proportions D. Z test for one population proportion E. 2 test of independence 2. What conditions must be met for the hypothesis test to be valid?

A. There must be at least 10 'success' and 10 'failure' observations. B. There must be an expected count of at least 5 for each cell in the table. C. There must be an observed count of at least 5 for each cell in the table. D. The data must come from a simple random sample. 3. Choose from the dropdowns to form the correct null and alternative hypotheses for this test. H0 : The variables Borough and Status are ? . Ha : The variables Borough and Status are ? . 3. State the degrees of freedom for this test. df= 4. Under the null hypothesis model, what is the expected count for reports from Staten Island that are Closed? expected count = 5. Calculate the contribution to the test statistic for reports from Staten Island that are Closed. contribution = 6. Calculate the test statistic for this hypothesis test. 2= 7. Based on the p-value, we have ? evidence that the null model is not a good fit for our observed data.