The iceberg has weight Wi = Mig and the buoyant force is equal to the weight of the displaced water, Ww = Mwg. Furthermore, since the iceberg is floating, its weight exactly balances the buoyant force:
Ww = Wi
Mwg = Mig
VwRhowg = ViRhoig
Vw = Rhoi/Rhow Vi
So, the fraction of ice underwater, Vw/Vi, is given by the ratio of densities Rhoi/Rhow=0.87. Over 87% of an iceberg's volume (and mass) is underwater. As you can see, the convenient definition of the gram gives us a quick way to see how much of a floating substance lies below the surface of fresh water: the fraction is equal to that substance's mass density in g/cm?.
Summary
<span>Archimede's Principle of bouyancy states that the bouyant force on an object is equal to the weight of the fluid displaced by that object.<span>The underwater fraction of a substance floating on water is given by that substance's mass density in g/cm3.</span></span>
Answer:
option A is correct ......marine or aquatic
Endosymbiotic theory has it that both chloroplasts and mitochondria were once free living organisms which got taken into bigger cells - they provide the cell with energy, while the cell provides them with proteins and other things.
The two things this question ask about support that theory: chloroplasts and mitochondria are surrounded by a double membrane, which makes sense in that they kept their original membrane and the little bit of the cell's membrane when it engulfed them. And they have some of their own genetic material, though most of it is non-coding, which they have kept from the time when they were independent organisms. Hope that's helpful.
