18. I The displacement of a wave traveling in the positive x-direction is y(x, t)=(3.5 cm) x cos(2.7x - 92t), where x is in m and t is in s. What are the (a) frequency, (b) wavelength, and (c) speed of this wave?20. I Figure P15.20 is a snapshot graph of a wave at t = 0 s. What are the amplitude, wavelength, and frequency of this wave? Figure P15.20 y (cm) 24 m/s Tx(m) -2 4 OC 12 16 2031. II BIO INT Sound is detected when a sound wave causes the eardrum to vibrate (see Figure 14.26). Typically, the diameter of the eardrum is about 8.4 mm in humans. When someone speaks to you in a normal tone of voice, the sound intensity at your ear is approximately 1.0 x 10 % W/m . How much energy is delivered to your eardrum each second?Figure 14.26 The structures of the ear. 1. Sound waves 3. . . . to the cochlea, enter the ear and the sensing area of cause the eardrum the inner ear, . . . to vibrate. Basilar membrane Eardrum Cochlea 2. Vibrations in the eardrum pass 4. . . . where vibrations in through a series the fluid drive vibrations of small bones . . . in the basilar membrane