Answer:
Time taken, t = 2.37 seconds
Step-by-step explanation:
It is given that,
Height of an object at time t is given by :

Where
v₀ is initial velocity of object
h₀ is initial height of the object
The feather is dropped from the top of the bridge 90 feet above a river. we have to find the time taken by the feather to reach the water.
At the surface of water, h(t) = 0 and v₀t = 0
So,

t = 2.37 seconds
The feather will take 2.37 seconds to reach the water surface.