Me asap.
what happens when a penny is dropped from a height of 20 meters?
its mass doubles for every second it falls.
the force of gravity causes it to accelerate.
it changes direction every 9.8 meters.
it falls at a constant velocity.

primary succession occurs in essentially lifeless areas regions in which the soil is incapable of sustaining life as a result of such factors as lava flows, newly formed sand dunes, or rocks left from a retreating glacier. secondary succession occurs