$A$ ball is rolled off the edge of a horizontal table at a speed of $4\, m/s$. It hits the ground after $0.4\, s$. Which statement given below is true?

$A$ ball is thrown upward from the top of a building at an angle of $30^{\circ}$ to the horizontal with an initial speed of $15 \,ms^{-1}$. If the ball hits the ground after $3 \,s$, then the height of the building is (acceleration due to gravity $= 10 \,ms^{-2}$): (in $\,m$)

An airplane is flying at a height of $490 \, m$ with a horizontal velocity of $60 \, km/h$. When the airplane is exactly above point $A$,a package is dropped from it. At what distance from point $A$ will the package hit the ground (in $/3 \, m$)? $(g = 9.8 \, m/s^2)$

$A$ ball is thrown upward from the top of a building at an angle of $30^{\circ}$ to the horizontal and with an initial speed of $20 \,m/s$. If the ball strikes the ground after $3 \,s$, then the height of the building is (acceleration due to gravity $g = 10 \,m/s^2$) (in $\,m$)

$A$ hiker stands on the edge of a cliff $490 \; m$ above the ground and throws a stone horizontally with an initial speed of $15 \; m/s$. Neglecting air resistance,find the time taken by the stone to reach the ground,and the speed with which it hits the ground. (Take $g = 9.8 \; m/s^2$).

$A$ stone is projected from a point on the ground so as to hit a bird on the top of a vertical pole of height $h$ and then attain a maximum height $2h$ above the ground. If at the instant of projection the bird flies away horizontally with a uniform speed and if the stone hits the bird while descending,then the ratio of the speed of the bird to the horizontal speed of the stone is