The researchers estimate that between 1990 and 2010, some 69 percent of the mass lost by the world's alpine glaciers can be traced to human influence – basically global warming. This 2013 file photo shows the Mendenhall Glaicer where it spills over the mountains above Mendenhall Lake in Juneau, Alaska.
The two differences you see when comparing the four chambers of the heart is that the arteries have a thicker wall and veins have thin walls and that the arteries carry oxygenated blood away from the heart which means they get more pressure than veins.
1.
B
Photosynthetic organisms require light, in which the sun’s rays can only go so far
2.
C
The energy flow pyramid goes from decomposers to producers, meaning that if producers are dying out due to lack of nutrients, there must be something wrong with the decomposer population