Scientists can determine if oxygen existed in earth's archean atmosphere by    a.  looking at the amount of salt content in rocks.  b.  looking for oxidized iron in rocks. c.  determining how many people survived. d.  determining the amount of outgassing that occurred.

An organism has the following traits multicellular cant photosynthesize has a skull. wht kingdom does this organism most likely belong too?

How is the carbon cycle related to global warming ?

In response to framton's dialogue about his health issues, mr. sappleton replies: "no? " said mr. sappleton, in a voice which only replaced a yawn at the last moment. then she suddenly brightened into alert not to what framton was saying. what does this statement reveal about how mrs. sappleton feels about framton? a) she finds him boring. b) she's happy he came by. c) she finds him annoying. d) she feels sorry for him