A human skull, on average, is about 0.3 inches thick, or roughly the depth of the latest smartphone. Human skin, on the other hand, is about 0.1 inches, or about three grains of salt, deep.
A human skull, on average, is about 0.3 inches thick, or roughly the depth of the latest smartphone. Human skin, on the other hand, is about 0.1 inches, or about three grains of salt, deep.