A student manages to get on the roof of a school and toss out a balloon with the speed of 10.0m/s. The height of the school is 25.0 m. How long was the balloon in the air?
The rate that it falls will depend upon its size and whether it is filled with helium, air or water. Air resistance will certainly be a factor, unless this is the proverbial "lead balloon". The answer will also depend upon whether the balloon is thrown up, down or sideways.
This is an absurd question, and you are wasting your time and tuition in such a class.