A rock is thrown downward from the top of a 36.2-m-tall tower with an initial speed of 13 m/s. Assuming negligible air resistance, what is the speed of the rock just before hitting the ground

It's because 3 if it was 10 it wouldn't look right do it goes up to 4d

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.