"D. It proved that black troops could fight bravely and well" is true about the 54th Massachusetts Regiment, which saw extensive action during the Civil War.
Britain had a lot of coal resources which helped them enormously develop and actually made it possible to some extent for Industrial Revolution to happen. But to mine coal was not an easy process. Coal was located deep underground and one the major problems was how to pump the water out of the mines. Only after the use of the steam pump did the process become somewhat easier.
In 1789 Congress created three Executive Departments: Foreign Affairs (later in the same year renamed State), Treasury, and war. It also provided fir an Attorney General and a Postmaster General. Domestic matters were apportioned by Congress among these departments.
Ans: As the first Roman emperor to claim conversion to Christianity, Constantine played an influential role in the proclamation of the Edict of Milan in 313, which decreed tolerance for Christianity in the empire. He called the First Council of Nicaea in 325, at which the Nicene Creed was professed by Christians.