Not sure about 1, but
2. The standard oil company became a huge company that put horizontal AND vertical integration into practice. The company made John D. Rockefeller the richest man alive at the time.
3. The meat inspection act made it a criminal act to mislabel meat that is being sold as food, and ensure that all meat being sold as food is slaughtered under sanitary conditions. The first event that out this process into to play was when Armour & Co supplied the US Army with rotten beef during the Spanish American War.
4. I guess you're talking about the Triangle Shirtwaist Factory Fire? This is significant because it is still one of the largest number of deaths from an industrial accident. The fire may have been an accident, but the number of deaths could have been prevented, for the company did not have a lot of safety precautions taken, there were locked doors all over the building which prevented 145 workers from living.
5. The 16th amendment gave Congress the power to tax income. The 17th amendment enforced the direct election of senators from the people.
6. The 18th amendment prohibited the sale of alcohol. Prohibition was significant because it sparked cultural changes, from people who started "speak-easies" and illegal alcohol sales.
7. The 19th amendment was huge for women, it gave them the right to vote. Women had been fighting for this for a long time. This amendment empowered women to step out to he workplace.
I'm sorry if I didn't answer it the way you needed it, but here ya go! ;)
The answer to that would be the President.
