He believed in it. That is why after the overthrow of the Russian tsar. He implemented marxist ideology into Russian politics and government.
Answer:
Running water and internal drainage systems were used to make them more safe and more sanitary to live in. The workers wages were also increased and workers could find jobs in the city.
The first one is the answer ;)
The answer is C. Having a secondary source from a time that an event occurred can help historians recreate and study the event.