Final answer:
Runner A had the fastest speed, Runner C had the slowest speed, and Runner C had a head start as indicated by the positions on the Position vs. Time graph.
Step-by-step explanation:
In a Position vs. Time graph, the slope of the line represents the velocity of the runner. A steeper slope indicates a higher velocity or speed. Since the blue line labeled A has the greatest upward slope, Runner A had the fastest speed in the race. Runner C, with the least slope, had the slowest speed.
Runner C also had a head start because his line intersects the vertical axis at a positive distance above 0 meters while lines A and B intersect at the origin, indicating that they started from the same position at the starting time.