Here's a formula that's so useful, you should memorize it:
Distance = (1/2) · (acceleration) · (time squared)
On Earth, acceleration of gravity is 9.8 m/s² .
Height of the bridge over the canyon =
Distance the truck falls = (1/2) · (9.8 m/s²) · (33 sec)²
Distance = (4.9 m/s²) · (1,089 sec²)
Distance = 5,336 meters