$A$ train running at the speed of $84 \, km/h$ passes a man walking in the opposite direction at the speed of $6 \, km/h$ in $4 \, s$. What is the length of the train (in $meters$)?

The distance between places $A$ and $B$ is $999 \text{ km}$. An express train leaves place $A$ at $6:00 \text{ am}$ and runs at a speed of $55.5 \text{ km/h}$. The train stops on the way for $1 \text{ hour } 20 \text{ minutes}$. At what time does it reach place $B$ (in $\text{pm}$)?

$50$ trees are standing in a line such that the distance between any two consecutive trees is the same. $A$ car takes $18 \, seconds$ to travel from the $13^{th}$ tree to the $34^{th}$ tree. How much time (in $seconds$) will it take to reach from the first tree to the $50^{th}$ tree?

$A$ person covers a certain distance in $6 \, hours$ if he travels at $40 \, km/h$. If he has to cover the same distance in $4 \, hours$,then his speed must be (in $km/h$):

$A$ train $200 \, m$ long is running at a speed of $20 \, m/s$. In how much time (in $seconds$) will it cross a bridge of $400 \, m$ length?

$A$ car is running at a speed of $108 \, km/hr$. What distance will it cover in $15 \, s$? (in $meters$)