Here's some great information on our Brachiosaurus.
Brachiosaurus was called the “arm lizard. It was one of the tallest and largest dinosaurs yet found. It had a long neck, small head, and relatively short, thick tail. Brachiosaurus walked on four legs and, like the other Brachiosaurids and unlike most dinosaurs, its front legs were longer than its hind legs. These unusual front legs together with its very long neck gave Brachiosaurus a giraffe-like stance and great height, up to 40-50 feet (12-16 m) tall.
Brachiosaurus had a claw on the first toe of each front foot and claws on the first three toes of each rear foot. Like other Brachiosaurids, it had chisel-like teeth, its nostrils were on the top of its head, and it had large nasal openings indicating that it may have had a good sense of smell. Brachiosaurus had 26 teeth on its top jaw and 26 on the bottom for a total of 52 teeth towards the front of the mouth. Brachiosaurus was an herbivore, a plant eater. It probably ate the tops of tall trees with its large spatulate (chisel-shaped) teeth. It swallowed its food whole, without chewing it, digesting the plant material in its gut.