Summarize the different photosystems in photosynthesis

How do you date a sample of rock that you suspect as being one of the earliest on earth

Predict the results of a two base insertion or deletion in a strand of dna that codes for a protien, how does this differ from a three base insertion or deletion?

Astudent reads the following text in a science book: scientific evidence tells us that the cause of earths four seasons is the tilt of earth as it revolves around the sound the student is instructed to illustrate this information in a science book. how will the student illustrate winter in the northern hemisphere? a. earths northern hemisphere will tilt away from the sun. b. earths northern hemisphere will tilt toward the sun. c. earths orbit will be farther away than from the sun d. earths southern hemisphere will tilt away from the sun.