Which of the following statements is true?

groundwater is not part of the water cycle.
most of the earth's water is freshwater.
refining oil pollutes the air with nitrogen dioxide.
thermal pollution is the main disadvantage of hydroelectric power.

Refining oil pollutes the air with nitrogen dioxide.

Explanation:

The refining of oil such as crude oil like petroleum producing a large amount of toxic gaseous waste in which the nitrogen dioxide is the one. The nitrogen dioxide is a chief pollutant of air. It contributes to the modification and formation of other air pollutants for example, ozone and particulate matter, it also the chief component of acid rain.

for 8 am not sure maybe yes?

for 9 if it is asking if the male is more or less it would be less

hope i even just a little : )

the generally accepted parts of modern cell theory include: all known living things are made up of one or more cells. all living cells arise from pre-existing cells by division. the cell is the fundamental unit of structure and function in all living organisms.