Yellow Cab - Mobile, Al
The FCC Data Files in RR for Mobile, Al show the following:
MOBILE CAB & BAGGAGE CO INC DBA YELLOW CAB CO WNCM842 152.42000
Generally, any VHF frequency between 152.270 and 152.450 is the base frequency for cab companies. There may be a group of frequencies in 450-455 or 460-465 range that are/were set aside for Taxi companies, but I don't know or remember what they were. In the UHF range, any frequency that is for regular businesses could be used!