You are riding in a train that is traveling at a speed of 120km /h how long will it take to travel 950 km

You divide 120 from 950 and that's the number of hours, 7.9

One traditional view of the mangrove forests that I know of is that they're kind of wasteland, not valuable to humans (also not good for farming). People would see the mangrove forest rather as a problem than a necessary ecosystem. Because of this, they would not protect them and perhaps use as a place to dump waste, which is one of the reasons why they're experiencing degradation.