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A researcher is studying whether living near a park affects physical activity levels. They collect information about daily step counts from people who live within 1 mile of a park and people who live more than 3 miles from a park. Which statement correctly identifies the components of this observational study?

A consulting firm analyzed the annual revenue growth (%) of 15 small businesses in a metropolitan area. Revenue Growth (%): -12, -8, 4, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18 Calculate the mean and median revenue growth. Which statement correctly compares these measures of center?

In a regression analysis of customer satisfaction versus wait time, the standard error of the residuals is 0.5 on a 5-point scale. What does this tell us about the model’s predictions?

A restaurant’s daily lunch revenue follows a normal distribution with mean $800 and standard deviation $100. Using the empirical rule, approximately what percentage of days will have revenue between $600 and $1000?

A financial advisor is analyzing the annual returns of different mutual funds.   Monthly Returns for 2024 (in percentages) Fund A: -2 15 12 -5 18 4 9 22 -8 16 7 12 Fund B: 6 9 7 10 5 8 11 7 9 6 8 10 Calculate the standard deviation for both funds and determine which statement is correct about their variability.

The table below shows the number of state-registered automatic weapons and the murder rate for several Northwestern states.   x 11.9 8.4 6.7 3.9 2.6 2.7 2.3 0.3 y 13.9 11 9.6 7 6.3 6.2 6.2 4   x = thousands of automatic weapons y = murders per 100,000 residents   Use the data from the table to calculate the line of best fit.

You have collected data on the number of text messages sent daily by 25 students: 45, 23, 67, 89, 34, 56, 78, 45, 34, 23, 67, 89, 90, 45, 34, 67, 78, 56, 45, 34, 23, 67, 89, 78, 56   Which type of graph would be most appropriate to show the distribution of daily text messages?

What is the correct order of the statistical investigative process?

When examining a scatterplot with a line of best fit, a data point falls above the line. What does this tell you about the residual for this point?

A neighborhood grocery store collects data about shopping patterns. They find that 60% of customers buy fresh produce and 25% buy organic products. If these events are independent, which of the following must be true?