Atrain 471 m long is moving on a straight track with a speed of 75.1 km/h. the engineer applies the brakes at a crossing, and later the last car passes the crossing with a speed of 15 km/h. assuming constant acceleration, determine how long the train blocked the crossing. disregard the width of the crossing. answer in units of s.

Tell me the answers for your question and you!

You need to be more specific.  i really don't know what a "motion map" is.you can draw a graph of an object's position, distance, displacement, speed,velocity, or acceleration versus time, or you can draw a graph of the object's x-position versus its y-position and not give any information about time at all.if the graph presents position or displacement against time,  then constant velocity is a straight line . . i.e. a line that has  constant slope.if the graph shows speed against time, then constant velocityis a horizontal piece of line.if the graph shows acceleration against time, then constant  velocity is a piece of line that lies on the x-axis . . it's value is zero.