The Cook County Board of Commissioners approved a measure Thursday that will compare the costs involved in maintaining or merging two software systems used for property tax administration. Meanwhile, a measure that would allow ticket prices and parking rates to increase at Brookfield Zoo will be heard in a Forest Preserve District committee. Chicago City Treasurer Melissa Conyears-Ervin gave her annual State of the City Treasurer’s Office address Thursday. And state officials gave an initial OK to the temporary Chicago casino.