Answer: 1, 2, 4 are accurate.
Explanation:
1. Joe is on a hill (on a trail) above the ocean. The beach and ocean are at similar altitudes. Therefore Joe is at a higher altitude than if he was at the beach.
2. Since Joe is on a hill, he has a higher altitude than at sea level. Air at a higher altitude has lower density because there is less air "ontop" of itself than at lower altitudes. As well, his hill is above the ocean, which means there is a lot of water, making the air more humid than where he is. Humidity also makes air denser.
4.The air pressure will decrease if Joe goes up to higher altitudes because there will be less air on top of itself.
They are dangerous to the environment because they have no natural competition. That being said they have nothing to keep their population in check, therefore, taking away food, and habits from all the other species. Thus, causing species to die out, which in turn ruins the food chain.
<span>The smallest unit that can evolve is a _____. cell</span>