Answer:
Seconds
Explanation:
This situation can be modeled using the vertical motion model, which is
y = -16t² + v₀t + h₀,
where t is the time in seconds, v₀ is the original velocity and h₀ is the original height.
The reason this is seconds is because it does not take long for an object thrown through the air or dropped from a cliff to fall; it would not take minutes or hours, but would take seconds.