what is the oval window in your ear
Oval window The oval window (or fenestra vestibuli) is a membrane-covered opening that leads from the middle ear to the vestibule of the inner ear.
Small intestine Food from the stomach is allowed into the duodenum through the pylorus by a muscle called the pyloric sphincter.
Marcus Álvarez
Limit of a function (the Dirichlet function) has no limit at any x-coordinate.