The major purpose of the iris in the eye in terms of the
visual system is focusing the light on the retina as the iris is responsible of
managing the light passing or reaching in the retina of the eyes.
Sedimentary rocks are formed by cementation and compaction. This happens when sediment particles are compressed and fused together over very long periods of time.
Whenever any atom becomes more positive, that means that it loses a negative charge. The subatomic particle that has a negative charge is the electron.
I’m not really sure but I’ve read through the answers so I think it’s A, B, and D. hope i helped !!