Question: In the ear of mammals: 
 Options:  <1> The sterocilies of the hair cells contact the basilar membrane. <2> The tympanic ramp contains endolymph. <3> The basilar membrane is wider and more flexible at the level of the helicotrema. <4> The sensory cells are those of Deiter. <5> The oval membrane has a larger surface than the tympanic membrane.
3