Answer
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Work Step by Step
Consider the ways in which the September 11 terror attacks could have affected traffic and driving habits, then decide what likely caused the increase in fatal traffic accidents in the final three months of 2011.
The September 11, 2001 terrorist attacks likely caused an increased fear of flying nationwide. As a result, more people opted to drive long distances as opposed to flying. With more people driving long distances there is more chance for fatal traffic incidences to occur. Figure 0.4 shows the effect of an increased number of people driving long distances on the number of fatal traffic accidents.
