If cyanobacteria had failed to appear on earth, how would the evolution of earth's atmosphere most likely be different

According to social exchange theory, altruistic behaviors benefit the individual who performs them.

This punnett square shows the cross between two pants. one parent has round seeds (rr). and the other parent has wrinkled seeds (rr) which best describes their offspring as shown in this cross?

Astudent pushes a 60-n block across the floor for a distance of 10 m. how much work was done to move the block