Answer
a. 8 AM
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b. 12 AM (midnight)
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c. Starting at 6 AM, there is a steady increase in traffic until it peaks at 8 AM before decreasing until 3 PM at which point it increases for a second peak at 5 PM then steadily decreases to a low overnight level
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d. Traffic pattern through the intersection is possibly related to work schedules of the population
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e. Run the same experiment on a Sunday
Work Step by Step
a. Highest number at approximately 57 cars passing through the intersection per hour
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b. Lowest number at 1 or 2 cars passing through the intersection per hour
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c. See graph pattern where a positive slope is observed from 6 AM to 8 AM followed by negative slope until 3PM. Then another positive slope from 3 PM to 5 PM before a final negative slope from 5 PM to 10 PM where a level slope is observed for the overnight time period.
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d. Work schedules is one potential guess. As long as you can provide justification (ex. most work days start at 9 AM and end at 5 PM) a hypothesis is an educated guess!
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e. See above. In the given example, most of the general population is assumed to stay at home during the weekend rather than commuting to work which would impact the number of cars passing through the intersection.