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4
CH1011
THE EARTH
1) Geosphere   (Core, Mantle)
Crust                0-   40 km           r = 2700kg/m3
 - O, Si, Al, Fe, Ca
2) Hydrosphere
Freshwater     0.7% (vol)
Ice                   2.0%
Seawater      97.3%                    r = 1030kg/m3
-  Na+, Cl-, Mg2+, SO42-
3) Atmosphere             
Stratosphere 15- 50 km  9% (mass)
Troposphere  0- 15 km  90%       r = 1.3kg/m3
 - N2, O2, H2O, Ar