Dinosaurs were abundant during

The reptiles,like dinosaurs,were dominant in the . . . . . . period.

$A$: $Tyrannosaurus$ $rex$ had fearsome dagger-like teeth.
$R$: $Tyrannosaurus$ was the largest dinosaur depending upon herbs and shrubs.

The $Mesozoic$ era of the Earth is known as the:

What are dinosaurs?

Mammals evolved from therapsid reptiles in the $Triassic$ period. The type of skull in these reptiles is