When do animals cooperate with one another?

What did not occur in the proterozoic eon a)the oxygen levels increase greatly in the atmosphere, b)the emergence of the eukarya , c)muti cella’s eukaryotic organisms began to diversify, d)anaerobic bacteria kept thriving with more oxygen

Where is having brightly colored feathers that attract mates most clearly an adaptation for a bird? a. a forest with dense vegetation b. a sandy beach beside an ocean c. a snowy tundra with little vegetation d. a swamp with many hawks that eat birds

If a force of 40 newtons moves a cart a distance of 9 meters, the work done is nm. if the same force moves the same cart three times that distance, the work done is nm.