Juanita sticks a nail to the end of a bar magnet. She then sticks a second nail to the first, then another to that one, and so on. When she gets to the seventh nail, it falls off the sixth nail.
Which statement best describes the forces acting on the seventh nail?
The force of magnetism is equal to the force of gravity.
The force of gravity is stronger than the force of magnetism.
The force of magnetism is stronger than the force of gravity.

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. 

It is either a  proton or a neutron im almost positive. hope this .