Can someone pls help

Seed plants that lived during the carboniferous impact life on earth today because a. they are the ancestors of all plant life on earth. b. their remains formed coal, which is an important resource. c. they produced fossils that are used to date many geologic events. d. their presence caused oxygen levels to drop, allowing animals to evolve.

How did the europeans design the national borders of africa? why?

Which environment would most likely not contain fossils? a a thick deposit of cracked, dried mud b sediment deposited in a sandy river bed c intrusive rock formed from cooled magma d layers of sand accumulated for a century