Answer:
look up information regarding 4 dinosaurs in the cretaceous, jurassic and triassic periods
Step-by-step explanation:
Cretaceous period:
Albertaceratops
Albertosaurus
Ampelosaurus
Anchiceratops
Jurassic Period:
Agilisaurus
Allosaurus
Apatosaurus
Archaeopteryx
Triassic Period:
Chindesaurus
Herrerasaurus
Guaibasaurus
Thecodontosaurus
Now, you do not have to use the dinosaurs that I chose. Just find some dinosaurs and then find some info regarding each one. I have a site that you can use in order to help:
look up each period and dinosaurs (triassic period dinosaurs) and click on the site that has a timeline. (it's called nhm.ac.uk)
good luck :)