A good person who got caught in a unworkable situation, Herbert Hoover was President from 1929-1933. As mentioned before, he had The Great Depression happen during his watch, but didn’t cause it.
The Cretaceous (along with the Mesozoic) ended with the Cretaceous–Paleogene extinction event, a large mass extinction in which many groups, including non-avian dinosaurs, pterosaurs, and large marine reptiles, died out, widely thought to have been caused by the impact of a large asteroid that formed the Chicxulub crater in the Gulf of Mexico.