Answer:
22 seconds
Step-by-step explanation:
The maximum height is at the vertex of the parabola.
For a parabola y = ax² + bx + c, the vertex is at x = -b/(2a).
Here, a = -16 and b = 704.
t = -704 / (2 × -16)
t = 22
It takes 22 seconds for the projectile to reach its maximum height.