The critical angle for a beam of light passing from water into air is 48.8°. this means that all light rays with an angle of incidence in the water that is greater than 48.8° will be

Which principle states: "geologic processes taking place on earth today operated similarly in the past and can be used to explain past geologic events"? a. lateral continuity

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.