What are the most common shapes of lunar craters, and why?

Lunar craters are craters on Earth’s Moon. They are formed by impacts. Impact happens when a planet’s surface is strucked by a meteroid. Their most common shapes is circular, due to material flying out in all directions, not because of the circular shape of the object (the impactor).

Full change in the electric plus system

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.