A, B, and C are three successive points on a straight line. AB = 6.0 m, and BC = 10.0 m. A small object moving along this line from rest with uniform acceleration, passes B and C, 2.0 s

and 4.0 s, respectively, after passing A. Calculate the

i)

acceleration of the body,

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.