Constantine issued the Edict of Milan. What did this do?

How did tyrants attempt to gain the approval of common citizens?

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.

What event, more than any other led to wwi?