How tall were brontosaurs'?
Brontosaurus
Brontosaurus (/ˌbrɒntəˈsɔːrəs/[1][2]; meaning "thunder lizard" from Greek βροντή, brontē "thunder" and σαῦρος, sauros "lizard") is a genus of gigantic quadruped sauropod dinosaurs. Although the type species, B. excelsus, had long been considered a species of the closely related Apatosaurus,[3] researchers proposed in 2015 that Brontosaurus is a genus separate from Apatosaurus and that it contains three species: B. excelsus, B. yahnahpin, and B. parvus.[4]