Answer:
we can explain all of these easily
Mass production of steel, large suspension bridges, steel frame construction in buildings. It allowed impurities to be removed cheaply and easily, enabling steel to be produced in mass quantities.
It would be C. the roman empire persecuted christians
A - The Confederates relentlessy attacked the fort.
On April 12, 1861 the Confederates bombarded Fort Sumter for 34 hours before Union forces agreed to evacuate. There were no fatalities on either side.