Dinosaurs had a varied diet depending on their species. Some were carnivores and hunted and ate other animals, while others were herbivores and only ate plants. There were also some dinosaurs that were omnivores and ate both meat and plants.
The exact cause of the extinction of dinosaurs is still debated by scientists, but it is believed that a combination of factors played a role. Some theories include a massive asteroid impact, volcanic activity, and climate change. The extinction of dinosaurs opened up new ecological niches for mammals, which eventually led to the evolution of humans.
The largest dinosaur ever discovered is currently believed to be the Argentinosaurus, a long-necked herbivore that lived in what is now Argentina during the Late Cretaceous period. It is estimated to have been about 100 feet long and weighed up to 100 tons.