(a) If a penalty is specified in the notice of a violation, a respondent may plead guilty by returning the notice of a violation and a check or money order in the amount of the specified penalty by mail to the address set forth on the notice of violation within 20 days of the date of service.
(b) In the event a respondent pleads not guilty, or fails to plead, or if no penalty is specified on the notice of a violation, a hearing on the notice of violation will be scheduled.