Agriculture was key to the development of modern "civilization" because by being able to grow food rather than getting it through trade or hunting, people were able to stay in one place instead of having to be where the food was. This also led to jobs because people became highly skilled in growing crops.
Mountains made it hard to find flat land.
The United States and Russia were in competition with each other to build up the most nuclear weapons. With this, elevated aggression and threats brought the two countries closer and closer to full out war. Russia saw Cuba as a prime target to build missile sites for nuclear warheads as it was so close to Florida, the United States wouldn't have time to react to the nuclear strike.
Answer:
In the Battle of Trenton (December 26), Washington defeated a formidable garrison of Hessian mercenaries before withdrawing. A week later he returned to Trenton to lure British forces south, then executed a daring night march to capture Princeton on January 3.
