If a ball can be thrown to a maximum horizontal distance of $80 \, m$,what is the maximum height to which it can be thrown (in $, m$)?

$A$ player kicks a football with an initial speed of $25\, ms^{-1}$ at an angle of $45^{\circ}$ from the ground. What are the maximum height and the time taken by the football to reach the highest point during motion? (Take $g = 10\, ms^{-2}$)

$A$ ball is thrown from the location $(x_0, y_0) = (0, 0)$ of a horizontal playground with an initial speed $v_0$ at an angle $\theta_0$ from the $+x$-direction. The ball is to be hit by a stone,which is thrown at the same time from the location $(x_1, y_1) = (L, 0)$. The stone is thrown at an angle $(180^{\circ} - \theta_1)$ from the $+x$-direction with a suitable initial speed $v$. For a fixed $v_0$,when $(\theta_0, \theta_1) = (45^{\circ}, 45^{\circ})$,the stone hits the ball after time $T_1$,and when $(\theta_0, \theta_1) = (60^{\circ}, 30^{\circ})$,it hits the ball after time $T_2$. In such a case,$(T_1 / T_2)^2$ is. . . . .

For a body projected at an angle with the horizontal from the ground,choose the correct statement.

Two paper screens $A$ and $B$ are separated by a distance of $100 \,m$. $A$ bullet penetrates $A$ and $B$ at points $P$ and $Q$ respectively,where $Q$ is $10 \,cm$ below $P$. If the bullet is travelling horizontally at the time of hitting $A$,the velocity of the bullet at $A$ is nearly .......... $m/s$.

For an object projected from the ground with speed $u$,the horizontal range is two times the maximum height attained by it. The horizontal range of the object is ..........