Astudent has been measuring the oxygen levels in a lake for one year. at the end of the year she graphs he oxygen levels by month. this is an example of which step of the scientific method?

This step is called analysis.

Explanation:

Analysis is when you record observations and analyze the meaning of the data. Often, you'll prepare a table or graph of the data.

well we can't tell you because we cant see the time give a screen shot or something.

sulfur dioxide

explanation: acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. these substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain.