The presence of is the key difference between gray and white matter.

I believe it is the "myelin sheath." White matter = myelinated (has myelin sheath), while gray matter = unmyelinated (no myelin sheath)!

The answer should be geothermal i hope i’m right message me if i’m wrong and i’ll change my answer and fix it for you

The truman doctrine was an american foreign policy whose stated purpose was to counter soviet geopolitical expansion during the cold war. it was announced to congress by president harry s. truman on march 12, 1947, and further developed on july 12, 1948, when he pledged to contain threats to greece and turkey