The period marked the completion of pangaea's breakup and was concluded by a mass extinction event.
a. permian
b. tertiary
c. jurassic
d. cretaceous

Which examples are relevant sources for students to use in research? check all that apply. a journal entry written by a professor who is considered an expert a report written by an independent government source a presentation by a company that includes paid information a document published by a renowned organization a scientific paper put out by a non-profit organization a blog whose author tries to sell a product or service