Compare and contrast the mass extinction event at the end of the Permian

From the third and fourth e-Activities, compare and contrast the mass extinction event at the end of the Permian (~250 Mya) with the mass extinction event at the end of the Cretaceous (~65 Mya). Include a discussion of the causes, the type of life forms impacted, the extent of the extinction, and the probability of a similar event occurring in the future.