The velocity-versus-time graph for a shuttle bus moving along a straight path is shown in figure 13. b. identify the time intervals during which the acceleration of the shuttle bus is constant. c. find the value for the average velocity of the shuttle bus during each time interval identified in b. d. find the acceleration of the shuttle bus during each time interval identified in b.

Since the Figure is not given let me answer the items above by concept. 
(b) The intervals during which the acceleration of the bus is constant is the portion where the graph is a line that is neither horizontal or vertical. 

(c) The area bounded by the curve and the x-axis is the distance. To get the average velocity, determine the total distance and divide by the total time interval.
 
(d) The acceleration is determined by calculating the differences between velocities and dividing this difference by the difference of time interval.

The answer to your question is 25hope this !