NEED HELP ASAP Which process do scientists think provided Earth with an oxygen-rich atmosphere?

radiometric dating

spontaneous generation

photosynthesis

respiration

What are the three major branches of natural science? • earth and space science, life science, physical science •earth and space science, physical science, chemistry •physical science, life science, chemistry •life science, chemistry, physics

This chart lists four kinds of polymers and their sources. what can be known about all four polymers, despite their differences? they come from living things. they share ionic carbon bonds. they are at least 100 monomers long. they are made of repeating subunits.

If an area has high air pressure and low humidity, what type of weather will it most likely have? plz !