1. Most workers lived in cities in extremely crowded buildings
Many people, and families, moved into the city to search for new jobs in the newly developed factories. As a result, cities services, as well as housing, were not prepared for this drastic population change.
2. Most workers worked long hours in low-paying industrial jobs
Many workers were forced to work 12 hours a day, 6 days a week, with very few breaks or holidays.
3. Led to an increase in population in the cities
As a result of the newly built factories, many people scurried to the city, in search of new jobs, resulting in a drastic population increase.
4. I'm not completely sure about this one but I'm pretty sure the answer is: the Triangle Shirtwaist Fire
The Triangle Shirtwaist Factory Fire opened peoples' eyes on the absurd working conditions in factories. This deadly fire left 146 dead and 78 injured.
5. steel
Steel is an incredibly strong metal, often used to help support large or tall buildings.
6. a lack of safety concerns for workers
When workers would take a break from working on a building, they wouldn't be given a comfortable or even safe place to sit. Instead, they sat on the steel beams of the building, hundreds, sometimes thousands, of feet up in the air.
I hope this was able to help you! :)