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the state in which one object's distance from another is changing
a place or object used for comparison to determine if an object is in motion
International System of Units
a system of measurement based on muliples of ten and on established measures of mass, length, and time
the basic SI unit of length
the distance an object travels per unit of time
the overall rate of speed at which an object moves; calculated by dividing the total distance an object travels by the total time
the speed of an object at one instant of time
speed in a given direction
the steepness of a line on a graph, equal to its vertical change divided by its horizontal change
one of the major pieces that make up Earth's upper layer
theory of plate tectonics
the theory that pieces of Earth's outer layer are in constant motion
the rate at which velocity changes
"Mary has chosen the good portion, which shall not be taken away from her."