President-elect Barack Obama has introduced four more nominees for his future economic team. Hilda Solis is the nominee for Secretary of Labor. Solis is a member of the House of Representatives from California and serves as vice chair of the Environmental and Hazardous Materials subcommittee of the Committee on Energy and Commerce. Ray LaHood is Obama's choice for Secretary of Transportation. LaHood is a retiring members of the House of Representatives from Illinois; he served on the House Appropriations and Transportation Committees. Ron Kirk of Texas is the nominee for United States Trade Representative. He has previously served as Texas Secretary of State and as mayor of the city of Dallas. Karen Gordon Mills is Obama's choice to head the Small Business Administration (SBA). Mills is president of MMP Group, a private equity investment firm in Maine; she also serves as chair of Maine Governor John Baldacci's Council on Competitiveness and the Economy, and on several corporate and nonprofit boards.