Most major European cities are located either on the sea or on a navigable river. This helped keep the city connected to the rest of the country and world, and offered more shipping and economic opportunities.
The correct answer is - mudslides.
The hurricanes bring in a very large amount of water with them in a very short period of time. Because of this, the soil gets over-saturated with water, and this causes the surface layer of the soil to start moving. The mudslides usually appear at steep places, and they are combination of large amounts of water and soil that have mixed and created fast moving mud river. The mudslides, because of there speed and sudden appearance, are extremely dangerous, and they cause very big damage, both in human lives and material damage.
They really help in the process of Africa's state building, creating commercial networks between parts of the continent, and introducing literacy ( especially on northern part of Africa)
They also controlled the sea route between Asia and Africa and managed to maintain the relationship between Africa and the middle east
Trees take in carbon dioxide and other gases that we cannot breathe in and gives us oxygen. It also helps other plants and animals nourish themselves. To some animals, trees are their habitat so by planting more trees, we are technically building a habitat for plants and animals to live in. It's also good shade on a sunny day.
