The horizontal range and the maximum height of a projectile are equal. The angle of projection of the projectile is

$A$ grasshopper can jump a maximum distance of $1.6 \; m$. It spends a negligible amount of time on the ground. How far can it go in $10 \; s$?

$A$ cricket ball is thrown at a speed of $28 \; m/s$ in a direction $30^{\circ}$ above the horizontal. Calculate:
$(a)$ the maximum height,
$(b)$ the time taken by the ball to return to the same level,and
$(c)$ the distance from the thrower to the point where the ball returns to the same level.

$A$ ball $P$ is dropped vertically and another ball $Q$ is thrown horizontally with the same initial vertical velocity (which is $0$) from the same height $h$ at the same time. If air resistance is neglected,then:

Two paper screens $A$ and $B$ are separated by a distance of $100\,m$. $A$ bullet pierces $A$ and then $B$. The hole in $B$ is $10\,cm$ below the hole in $A$. If the bullet is travelling horizontally at the time of hitting $A$,then the velocity of the bullet at $A$ is $.......\,m/s$.

The angle of projection at which the horizontal range and maximum height of a projectile are equal is