How Does the Global Economy Depend on a Single River?

Imagine a river that acts like a superhighway. It carries goods from one country to another, just like cars on the road, but instead of cars, it carries boats full of food, machines, and even money. The Nile River is one such superhighway for Africa and parts of Europe, and if something happens to it, like a big flood or drought, it can make life harder for millions of people who depend on it.