The answer is that <span>all
veins carry blood back to the heart, except for the pulmonary vein. the
vena cava empty into the right side of the heart, so they technically
bring blood to the
</span>main atrium.
The answer is A, a mountain building.
The two faces of the book represent the tectonic plates
As he presses them towards each other he is modeling a convergent boundary, and mountains are an affect of convergent plates.
It is strengthened by data which is always contradictory.
the large intestine primarily
They are both important because mechanical has to do with physical - cause mechanical means physical, so chewing your mouth is physical (you break your food into smaller pieces physically). And then chemical digestion is when food and saliva mix together. They happen when breaking down food into nutrients - enzymes. Enzymes are important for that process, because they make a nutrient.
Hope this helps!!