We can set up a proportion here:
38 km / 1 hour = 142.5 km / x hour
x is the unknown time we want to find.
Cross multiply:
38*x = 142.5
Divide by 38 from both sides to get:
x = 3.75 hours
Answer:
the answer might be
agriculture I'm not sure get a try tar
Many primary civilizations started in river valleys because for the cities in each civilization an important portion of the population existed in cities. Large-scale farming was a requirement to feed the large populations. Fertile due to flooding the land by rivers was home to lush plant life and an outstanding place to plant and grow crops. The close source of water permitted for irrigation for the large-scale farming as well as drinking and bathing. Water also intended animals and animals meant food so this was another advantage to settling in river valleys. Settling and living in river valleys later main to further development of civilizations and new patterns of living such as trade and communication by means of the river for transportation.
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.
