Do you have a picture of the diagram that I could view?
Answer:38.675 m/s
Explanation:

t=4.2 s

Solving in x direction


ucos25=25
u=27.584 m/s
Initial velocity in vertical direction usin25
Let h be the height of Rooftop

h=37.47 m
Therefore final vertical velocity is 
=29.51 m/s
Final Resultant velocity


In a collision an object experiences a force for a specific amount of time, which results in a change momentum(the objects mass may ethier speed up or slow down). Impulse will be produced because of force appiled to an object over a period of time.
Velocity is the speed of something in a given direction. I hope this helps and have a great day (Also brainliest would be appreciated but you don’t have to) :)