Answer:
this helped me in my test hope it helps you
Explanation:
https://youtu.be/oieXYuQm_xE
Possibility of acid rain will increase
Answer:
Survey
Explanation:
Because if you think about it carefully you really cant observe it. Your main goal is to compare them and with that we need a survey to get the data from both sides. Leaving us with the Survey
I believe the answer is linear :)