The chief of police shall:
(1) Schedule at least two law enforcement officers to be on duty at all times. While on duty, each officer must be able to communicate directly with the other and, if not engaged in another law enforcement activity, respond to the other officer’s request for assistance; or
(2) Establish a means for a municipal law enforcement officer to communicate with the county sheriff’s office and to request assistance of a routine law enforcement nature from the county sheriff’s office; or
(3) Establish a mutual aid agreement as provided in chapter 23 in order for a municipal law enforcement officer to communicate with municipal law enforcement agencies of other jurisdictions and to request routine law enforcement assistance from those agencies.