The twelve pairs of cranial nerves are continuous with the brain and are numbered from anterior to posterior, according to their attachments to the brain. CN-I is attached to the cerebral hemispheres. CN-II is attached to the central cerebrum via the optic chiasma (hypothalamus), CN-III and IV to the midbrain.
Hello wasn’t used as a greeting until many years later when the telephone was invented. Inventor Thomas Edison is given credit for suggesting the use of hello as a standard greeting when answering a telephone. Edison’s competitor, Alexander Graham Bell, had his own idea for a proper telephone greeting.