Why are Ravenstein's laws of migration changing?

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.

Asap! ! ! western china, northern china and southeastern mongolia are all located in what climate zone? tropical wetdesert humid subtropical humid continental

The process by which liquid water changes into water vapour is called what ?