I need help with my test review! (45 POINTS) 1. what can fossils show scientists?
2. how is mold different than a cast?
3.how is mold different than a cast?
4.what is a trace fossil?
5. how does mineralization occur? how does carbonization occur? how do molds and casts form? how do trace fossils occur? how does original material occur?
6. what is meant by the "Law of Supervision"?
7. What is "relative age dating"? How can it be done?
8.What is "absolute age dating?"
9. How does the "Law of Supervision" 'tell' us about relative age dating?
10.How many mass extinctions have there been?
11. what are some ways these extinctions may have happened?
12. why would these events cause extinction? (be specific)
13.how did plate tectonics 'help' evolution of species?
14. what is meant by "biological evolution"?
15.what is variation? (genetic variation)
16. How is artificial selection different than natural selection?
17. What can we study to show similarities and differences between organisms?
18. what is meant by survival of the fittest?

thinking it would be d not too sure but i think it's right

hypoxemia refers to a below usual concentration of oxygen in the blood, mainly in the arteries. hypoxemia is an indication of an issue associated with circulation or breathing and may lead to various symptoms like shortness of breath.  

the condition is identified by determining the level of oxygen in the blood sample obtained from an artery. it can also be predicted by determining the oxygen saturation of the blood with the application of a pulse oximeter.  

the normal arterial oxygen is about 75 to 100 mm hg. the values underneath 60 mm hg is generally considered with the requirement for supplemental oxygen. the normal pulse oximeter readings generally range between 95 to 100 percent. the values under 90 percent are regarded as low.  

in the given case, the oxygen saturation is measured at 93 percent, hence, there is no need to administer oxygen, that is, one should withhold oxygen.  

bacteria could be both, harmful and to us. harmful bacteria could make us sick and probably even by getting the chances of getting a disease, but good bacteria fight it off with your immune system. there is always bacteria everywhere we go. we need to make sure to wash our hands after using the restroom, before eating, after eating, after petting an animal too. so you see, bacteria is everywhere and is harmful or . i hope this . : ) : ) : )