The structure of Earth can be defined in two ways: by mechanical properties such as rheology, or chemically. Mechanically, it can be divided into lithosphere, asthenosphere, mesospheric mantle, outer core, and the inner core. The interior of Earth is divided into 5 important layers. Chemically, Earth can be divided into the crust, upper mantle, lower mantle, outer core, and inner core.
flat dollar. Definition. A description of an absolute amount, as opposed to an amount determined as a function of another amount, such as a percentage. Most Viewed.
Best Answer:  It means less than or equal to, that is 50 is the most that x can achieve. Another way to look at this is to consider the meaning of at least.. If you have at least 20 dollars, then the smallest amount of money you can have is this, so you have greater than or equal to 20 dollars.