roughly 65 degrees
They open it very wide.
You can't. You can only open your mouth as wide as your jaw will let you.
Open the mouth wide.
Birds
Wide open. A gaping hole is a wide open hole. A gaping mouth is one which is hanging open, usually from astonishment.
Very wide. Approximately 69m.
hippos can open there about 3 feet or more depending on the size
He stood there with his mouth gaped open, utterly shocked by what he had just heard.
Wide enough to swallow an average 4th grader.
It's physically impossible to swallow with your mouth wide open, as the act of swallowing involves your muscles closing off the airway to prevent food or liquid from entering the lungs. If your mouth is wide open, your swallowing reflex will not be triggered.
It was believed it could open it's mouth 120 degrees, which is more than snakes who have to dislocate their jaws to open them to about 100 degrees.