Plains.
Elevation
The height above sea level at any point on Earth's surface is referred to as the elevation or altitude.
Earths core
elevation
Earth's core
For any point on Earth's surface, its height above sea level is called elevation or altitude. This measurement helps to determine the vertical distance between the point and the average sea level.
That I believe, would be the Earth's Crust.
Moon
30 feet above sea level and 50 feet above earths surface... science homework these days
Yes it is.
a plateu
It is called altitude. It is typically expressed as ASL (above mean sea level, or MSL). However, it can also be specified as AGL (Above the local Ground Level).