Identify the point where the common ancestor of the fly and spider would be located.

The common ancestor of the fly and spider would be located in the closest where B and C converge.

Explanation:

In phylogenetic trees, two species are more related if they have a recent common ancestor. On the other hand, two species will be less related if their common ancestor is not a recent one and is located far away in the tree.  

In the phylogenetic tree, the taxonomic groups of interest are located in the extremes of the lines called branches. In the present example, the fly and the spider are the species located in the extreme of the branches. The ramification point, which is also called "node" or divergence point, represents the location of the most recent common ancestor.

In the example, the point where the branches B and C get united, is the place where their common ancestor is located.      

The red point in the attached file "tree1" shows you where it is located the common ancestor of the two species.                      

sand 60

clay 10

silt 30

sandy loam should be dominated by the sand. as the amount of sand increased, the amount of slit needed to anchor the plants' roots to the sand will also be increased. even though the amount is very little, 10% part of clay is still necessary for proper oxidation.

it has to be understood that the sea water contains a huge amount of sodium and chlorine ions and if they enter the cell of the atlantic cod fish, the cell will shrivel and the fish will die. to avoid such a condition, the fish uses active transport for the purpose of removing the ions against the gradient.

explanation:

the atlantic cod is not a maritime osmoconformer. its native application of salts is less than that of the seawater it lives in. it is continually falling water from the gills to the ocean via osmosis.

countering that, the fish is going to be swallowing seawater. but since its internal collection of salts is lower than seawater, the fish will want to go free of excess salt, and since that's going upon a gradient, then active transport, requiring energy, must be used to pump out the salt. much marine fish use the organs to filter out the salt and these fish discharge very straight urine.