<prompt> What is the length of external auditory canal?2.5 cm1.5 cm1cm2 cm  <response>: Ans. a 2.5 cmRefi Dhingras ENT 5th ed. 4 Length of external auditory canal- 24 mm 2.4cm Shape: S- shaped Outer 13rd cartilaginous part 8mm Inner 23rd: Bony part 16mm 