1. **State the problem:** We need to find the range of speeds tested from the given data set. 2. **List the speeds:** The speeds in miles per hour are: $$6.8, 7.1, 6.9, 6.8, 7.1, 7.1, 6.6, 6.8, 7.0, 6.6, 6.8, 6.8$$ 3. **Identify the minimum and maximum speeds:** - Minimum speed $= 6.6$ mph - Maximum speed $= 7.1$ mph 4. **Calculate the range:** $$\text{Range} = \text{Maximum speed} - \text{Minimum speed} = 7.1 - 6.6 = 0.5$$ 5. **Conclusion:** The range of speeds tested is $0.5$ mph.