It turns out that music on a record is filtered before being cut into the vinyl. the low frequency part of the music is attenuated (reduced in magnitude) and the high frequency part is amplified. this is done because the low frequency waves take up too much room on the vinyl, and would reduce the play time, and the high frequency is so low that it would be lost in the noise of the vinyl material. special preamplifiers (known as phono preamps) are used to reverse this process by amplifying the low frequency and attenuating the high frequency before sending the music to the speakers. the following bode plot represents the standard filter (in a phone preamp), known as the recording industry association of america (riaa) equalization curve, for playback of records 60 g 40 20 2 20 48 480 2100 freq (hz) assuming that all the poles and zeros for this filter are on the left-half-plane (lhp), what is the transfer-function for the this playback filter. for this problem only, you can leave the transfer-function in zero-pole-gain (zpk) form (s-1)(s - - zm g(s) k where zi represents the zero locations, p, represents the pole locations, and k represents the dc-gain