The body is thrown vertically upward at a speed of 30 m / s. What is the flight time of the body to the point of maximum height?

For a body thrown vertically upwards and provided there is no air resistance, the following formula is relevant:
H = (V ^ 2) / 2 * g
from the conditions of the task and the value of the acceleration of gravity:
H = (V ^ 2) / 2 * g = (30 ^ 2) /2*9.8=900/19.6=45.918
H = 45.918 m – the height of the body thrown vertically upwards
then t = H / V = 45.918 m / 30 m / s = 1.53 sec – body flight time