what was the kagest dinasour that has ever lived?

Answer 1

They're still finding fossilized fragments of very tall and very heavy dinosaurs : Argentinosaurus, Supersaurus, Sauroposeidon, Amphicoelias fragillimus, Bruhathkayosaurus.

Among the tallest and heaviest carnivourous dinos : Spinosaurus, Giganotosaurus, Mapusaurus, Tyrannosaurus rex and Carcharodontosaurus.

Answer 2

The title of largest dinasaur is open to dispute. For a good discussion see:

http://www.gavinrymill.com/dinosaurs/largest-dinosaur-ever.html

Answer 3

One of the sauropods, but no one is sure which one specifically was the largest.