It has opened new trade routes and we can see what they used for their roads and we can make ours better.
As you may know, trees are used to make things like furniture, cottages and paper. Unused paper is then 'thrown in the recycling bin' and recycled (go through the same system to be reused). Deciduous tree leaves specifically, fall off in Autumn so the sticks, trunk, and remains of the tree can be used to make products with the nutrients in the wood. I think this is part of an ecosystem - hope I help! :D
The best answer to this question is:
C. A forest fire that was caused by lightning.
A forest fire could kill for example all the individuals of a certain species in a given area - this would be independent of the population density of the species. All the other factors would affect the population the more, the more dense it is.
,
A. it is made up of rock so hot that it flows