According to a 2007 study, what was the average speed difference between trucks and automobiles?

Answer: B — 2 to 5 mph

The correct answer is based on data from the 2007 study, which indicated that the average speed difference between trucks and automobiles typically falls within the range of 2 to 5 mph. This range highlights the common operational characteristics of trucks as they tend to travel at slightly lower speeds than passenger vehicles due to their size, load, and safety regulations. Understanding this speed differential is crucial for drivers in anticipating traffic flow and for road safety measures, as it underscores the need for awareness when navigating roadways shared by both types of vehicles. This knowledge helps in planning trips and understanding timing on the road, which can be beneficial in various scenarios, including logistics and transportation planning.