Which feature is used to classify a rock based on its composition?

Which type of neuroglia is found outside of the brain?

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

The first generation of offspring from the cross of two parents is called the a. f1 generation b. f2 generation c. short generation d. p generation