Answer:
Labor union enable workers to voice concerns about working conditions and safety issues, making them more confident and less intimidated by their employers and thus more productive.
Labor unions foster a more stable work force, decreasing turnover.
Unions are always more efficient than firms at discerning which workers are highly skilled and which are not.
Step-by-step explanation:
Labor unions improve productivity by improving employee satisfaction, decreasing turnover and attracting trianed skilled labor