The body falls within 9 seconds. From what height did the body fall? How fast did it drop?

It is understood that the body began its motion with zero speed, falls on the Earth, and the friction force does not act on it.
Let us direct the 0y axis in the direction of body movement. Mark 0 corresponds to the position of the body at the original height.
Then the equation of its motion will have the form: y (t) = (g * t ^ 2) / 2 (where g is the acceleration of gravity (= 9.8 m / s ^ 2)). When the body reaches a certain point on our axis (corresponding to 9s of flight), it will fly the entire distance from its starting point to this point. Let’s denote the coordinate of this point (final) as h. Its value will be equal to the fall height for the selected time. Let’s substitute our data into the equation of motion. y (t) = h = (9.8 * 9 ^ 2) / 2 = 396.9 m.
The equation of speed for uniformly accelerated motion (and we have just this (g = const)) will have the form: V = g * t (the speed initially, by condition, was equal to zero). Let’s substitute the time value: V = 9.8 * 9 = 88.2 m / s (speed after 9 s fall).