The body was thrown upwards 50 m / s to find the height in 4 s.

To find the height of a given body after 4 s of flight, we apply the formula: S = h0 = V0 * t + a * t ^ 2/2 = V0 * t – g * t ^ 2/2.

Constants and variables: V0 – throw speed (V0 = 50 m / s); t is the considered flight time (t = 4 s); g (acceleration due to gravity) ≈ 10 m / s2.

Calculation: S = V0 * t – g * t ^ 2/2 = 50 * 4 – 10 * 4 ^ 2/2 = 200 – 80 = 120 m.

Answer: The body should reach a height of 120 m after 4 seconds of flight.