What defensive measure did the romans use to protect rome in the period of decline after the five good emperors?

Which two sets of political ideas speed as a result of the worldwide depression of the 1930s

The articles of confederation did not allow the government the power to tax or to force the states to do anything. what challenges could this cause

Why are slanted roofs found on many buildings within russia and finland? a. to prevent ice slides. b. to prevent the build-up of water during heavy rains. c. to prevent heat from escaping during the clod winter months. d. to prevent snow build-up.