(b) Every person convicted of a violation of this section shall be punished by a mandatory fine of not less than one hundred dollars ($100) nor more than one thousand dollars ($1,000) upon a first conviction, by a mandatory fine of not less than five hundred dollars ($500) nor more than one thousand dollars ($1,000) upon a second conviction, and by a mandatory fine of not less than seven hundred fifty dollars ($750) nor more than one thousand dollars ($1,000) upon a third or subsequent conviction. The court may, in addition to the fine imposed upon a conviction, require as a condition of probation, in addition to any other condition, that any person convicted of a violation of this section pick up litter at a time and place within the jurisdiction of the court for not less than eight hours.