The ratio of the distances travelled by a freely falling body in the $1^{\text{st}}$,$2^{\text{nd}}$,$3^{\text{rd}}$,and $4^{\text{th}}$ second is:

$A$ body is projected vertically upwards at time $t=0$ and it is seen at a height $H$ at times $t_1$ and $t_2$ seconds during its flight. The maximum height attained is ($g$ is acceleration due to gravity).

$A$ ball is thrown upwards. It takes $4 \, s$ to reach back to the ground. Its initial velocity is........$m/s$.

$A$ boy is standing on top of a tower of height $85 \, m$ and throws a ball in the vertically upward direction with a certain speed. If $5.25 \, s$ later he hears the ball hitting the ground,then the speed with which the boy threw the ball is .......... $m/s$ (take $g = 10 \, m/s^2$ and speed of sound in air $= 340 \, m/s$).

From $18 \text{ m}$ height above the ground, a ball is dropped from rest. The height above the ground at which the magnitude of velocity equals the magnitude of acceleration (in the same set of units) due to gravity is . . . . . . $\text{m}$. (Take $g = 10 \text{ m/s}^2$ and neglect the air resistance)

$A$ stone dropped from the top of the tower touches the ground in $4 \, s$. The height of the tower is about..........$m$.