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In a dataset of 800 salaries, an employee’s salary is at the 25th percentile. Which of the following statements are true? (Select all that apply.)

Use the Probit sheet. The Department of Health Services aims to predict whether an individual will receive an annual flu shot using a probit regression model based on community health survey data. As predictors, the model considers age (in years), income (in thousands), health insurance coverage (1 if insured, 0 otherwise), and length of residence (measured by the number of years the person has lived in their current zip code). The Probit sheet contains the descriptive statistics and probit regression results. What is the marginal effect of “length of residence” at the mean? Report as a percent without the % sign, four decimal places.

At the Nevermore Library, study sessions average 52 minutes with a standard deviation of 8 minutes. The session duration follows a normal distribution. Using the empirical rule, what percentage of sessions last between 28 minutes and 60 minutes? Please answer in one decimal place without the % mark.

If the total sum of squares (SST) is 2,850.1 and the sum of squares due to error (SSE) is 600.2, what is the r-squared value? Please round your answer to four decimal places.

At Erewhona, the average time customers spend waiting for a smoothie is 10 minutes, with a standard deviation of 2.5 minutes. Assuming wait times are normally distributed, what wait time (in minutes) corresponds to a z-score of +2.0? Round your answer to the nearest integer if necessary.

Use the WideAwakeCoffee sheet. What is the covariance between Foot Traffic and Cups Sold? Please round your answer to two decimal places.

If the total sum of squares (SST) is 2,850.1 and the sum of squares due to error (SSE) is 600.2, what is the r-squared value? Please round your answer to four decimal places.

Use the ChainSupermarketsB dataset. This is the same data as the ChainSupermarketsA dataset, provided again on a separate sheet. Create a pivot table. Based on the pivot table, which city has the highest average revenue per store?

Use the ChainSupermarketsA dataset. Create a pivot table. Based on the pivot table, which city has the lowest total transactions?

If all forecast errors are positive, which of the following statements must be true?