Answer:
C
Explanation:
the respiratory system and the circulatory system work closely together to deliver oxygen to cells and to get rid of the carbon dioxide the cells produce. The circulatory system picks up oxygen in the lungs and drops it off in the tissues, then performs the reverse service for carbon dioxide.
<span>the one that is not a factor that contribute to natural selection is : Population stability
population refer to the capability of a community to maintain its total amount of organisms within a specific period of time.
This has nothing to do with natural selection, which basically a nature's way to reduce the number of organism to findout which organisms are more adaptive</span>
The element cobalt can form compounds in two different oxidation states, +2 and +3.
The +2 state is more common.
The ion Co2+ (aq) is pink.
Other compounds of cobalt(II), which include both anhydrous Co2+ and complex ions, are commonly blue.
If an aqueous solution contains both cobalt(II) and chloride ions, the blue ion CoCl42- forms, in equilibrium with the pink Co2+ (aq) ion.
<span>CoCl42- (aq) <===========> Co2+ (aq) + 4Cl1-(aq)</span>