Final answer:
In the period 1964-1989, organized labor in the United States faced challenges and changes, but still fought for workers' rights.
Step-by-step explanation:
In the period 1964-1989, organized labor in the United States experienced various challenges and changes. During this time, the American Federation of Labor (AFL) and Congress of Industrial Organizations (CIO) merged in 1955. However, the overall percentage of workers who were part of labor unions declined due to factors such as the shifting economy, the relocation of corporations to anti-union states, and the passage of laws like the Taft-Hartley Act of 1947, which gave states the power to allow workers to opt out of the union. Despite these challenges, labor unions employed strategies such as collective bargaining and strikes to fight for the rights and safety of workers.