According to my test, The answer would be D. Hydrocarbons.
This may be wrong for some test. This was correct for my test.
Thank you.
Answer:
Descriptive investigations are not repeatable because they are based only on observations made at a single point in time. The results may vary at a different time. In addition, descriptive investigations do not contain variables that may indicate cause-and-effect relationships.
Explanation:
Choice D would be your answer
The answer is both open and close but it can only be one so i would go with d. open
Answer:
C. It releases oxygen and increases Earth oxygen supply.
Explanation:
Oxygen is the waste product of the photosynthesis.
