<span>So far, astronomers have found more than 500 solar systemsand are discovering new ones every year. Given how many they have found in our own neighborhood of the Milky Way galaxy, scientists estimate that there may be tens of billions of solar systems in our galaxy, perhaps even as many as 100 billion.</span>
Answer: b. Clear-cutting
Explanation: Clear cutting is a cheap and effective way of harvesting trees or timbers, this methods helps the forest operators to get the best out of a forest at a very reduced cost.
Clear-cutting is bad because removing the whole tree from an area destroys outrightly the natural habitat of most widelife, and it will also lead to the destruction of the eco-system that relies on the forest.
Answer:
1. Location
2. Place
3. Human-environment interaction
4. Movement
5. Region