Legalism would be the best way to go.
Hope it helps.
They are:
Executive: President and about 5 million others - The president enforces the laws.
Legislative: Senate and House of Reps - this part is called congress. Congress makes our laws. Congress is divided in 2 parts; senate and house of reps. Senate is made up of 2 people from each state. House of reps get together and decide if the bills should become laws.
Judicial: Supreme court and lower courts - hear cases that pertain to issues related to the constitution. They are the highest court in the country.
The three principal ways civilization spreads from one region to another is through trade, travel and warfare. When people travel, they bring with them goods from their region to another and this would be the start of contributing and sharing, and trading their ways and ideas of growing crops and raising other goods. It can also be spread through wars. Through this, different relationships emerged.
I believe you are referring to the evacuation of Saigon (Fall of Saigon) on April 30, 1975. If so, the correct answer is c. The U.S. evacuated Vietnamese whose lives would be in the greatest danger if they were to be left behind.
Grant and his Army of the Tennessee crossed the Mississippi River and drove the Confederate Army of Mississippi, led by Lt. Gen. John C. Pemberton, into the defensive lines surrounding the fortress city of Vicksburg, Mississippi.