D <span>investigating how the amount of annual precipitation affects the distribution of a tree species</span>
Answer: A
Explanation:
Oxygen makes up another 20 to 21 percent of our atmosphere. It's essential for life on Earth, and interestingly enough, it is poisonous when highly concentrated. Our concentration of 20 to 21 percent seems just right.
Answer:
B. increase biodiversity
It can't increase the biodiversity it can effect the biodiversity
Answer:
There is a positive relationship between environmental policies and jobs and the economy.
Explanation:
The conclusion of the studies is that environmental policies increase employment in the industrial sector. It is because for reducing pollution, the industries does not use heavy machinery for increasing production so these industries uses labour to maintain its production capacity and for more production more labour is required which decrease the problem of unemployment while economy also increases due to more production of products in the industries.
I honestly think it’s the second one
Sorry if I’m wrong