157- The velocity–time graph of a moving object along the x-axis is shown below. According to the graph, the average speed of the object during the time interval when the object moves in the negative x-direction is how many meters per second? [Figure: V(m/s) vs t(s) graph. The velocity starts at 2 m/s, decreases linearly, crosses zero at time t, reaches $-15$ m/s, then increases back to zero at $t = 25$ s.] (1) zero (2) $2.5$ (3) $7.5$ (4) $10$
\textbf{157-} The velocity–time graph of a moving object along the x-axis is shown below. According to the graph, the average speed of the object during the time interval when the object moves in the negative x-direction is how many meters per second?
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\textit{[Figure: V(m/s) vs t(s) graph. The velocity starts at 2 m/s, decreases linearly, crosses zero at time t, reaches $-15$ m/s, then increases back to zero at $t = 25$ s.]}
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(1) zero \hfill (2) $2.5$ \hfill (3) $7.5$ \hfill (4) $10$
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