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8. Five trucks are following one another in one lane in a convoy. How many headways can be ebserved from these 5 vehicles? C A. O B. 5 C. 4 D. 1 11) Five successive vehicles passed a reference point at speeds of 40, 36, 42, 44, 33 mph. What is the space-mean speed? D A. 38.23 mph B. 38.50 mph C. 38.75 mph D. 38.57 mph Ss