An object moves along a straight horizontal track. The graph shows the object's velocity \(v\) as a function of time \(t\) between \(t = 0\text{ s}\) and \(t = 4.0\text{ s}\). The curve is parabolic with its vertex at \((0\text{ s}, 2.0\text{ m/s})\) and passes through \((4.0\text{ s}, 10.0\text{ m/s})\). What is the average velocity of the object over the time interval from \(t = 0\text{ s}\) to \(t = 4.0\text{ s}\)?