Strong metal tools allowed bronze afe farmers to grow surpluse crops and trade them with neighbors for goods such as tools . the farmers needed a method for recording their exchanges and keeping track of how much surplus they had left.

Why might collective bargaining fail, causing a union to go on strike? a the union agrees with the boss about wages. b the boss compromises about work hours. c the factory goes out of business, causing the workers to lose their jobs. d the boss refuses to address dangerous working conditions in the factories.