An object dropped from the top of the tower and covered 25m at the last second , then find the height of the tower ?

The stone covers 25 m in the last second of its fall from top of a tower.

Distance covered in any one given second = Average speed of the body during that second × 1 second = ½ × (speed at the beginning of the second + speed at the end of the second) × 1 second=1/2 ( speed at the beginning of the last second is say u + speed at end of the last second is u + a ) × 1 second = ½ ( u + u+a )× 1 second= ( u + ½ a) × 1 second = ( u +5m/s²×1s) × 1 second (a = 10 m/s²=( u m/s + 5 m/s)× 1s.