O. ID 24-645 Consider adoption of an ordinance of the City of Denton, a Texas home-rule municipal corporation, authorizing the approval of a sixth amendment to a Professional Services Agreement between the City of Denton and Nelson + Morgan Architects, Inc., amending the contract approved by Purchasing on February 13, 2014, in the not-to-exceed amount of $24,840.00, amended by Amendments 1-5 approved by Purchasing and City Council, said sixth amendment to provide additional design services for the base project and additional design services of the HVAC system at Fleet Maintenance; providing for the expenditure of funds therefor; and providing an effective date (File 5497 - providing for an additional sixth amendment expenditure amount not-to-exceed $171,299.00, with the total contract amount not-to-exceed $541,698.97).