We have a fluid type, a liquid of a type known as the periomph. And as this air fluid boundary, we have a considerable amount of resistance to the mechanical waves. And to overcome this resistance, we have to amplify our force. And that's exactly we amplify the force at the pina. We then amplify the force at the ear drum, and we amplify the force at our three bones, the malleus, the incas, and the staples. Now, at the pina, we amplified by about times two.