Answer:1.624 m
Step-by-step explanation:
Given
height of 2nd floor =5 m
time recorded is 0.58 sec
Let h be the height of third floor above 2 nd floor

here u=0
t=time taken to cover height h
----------1
Now time taken to complete whole building length
----------2
Subtract 1 form 2

Taking gravity

1=(2t+0.58)(0.58)
t=0.57 s
Substitute the value of t in 1
h=1.624 m