$A$ person crosses a $600\, m$ long street in $5\, minutes$. What is his speed in $km/hr$?

$A$ train covers a distance of $12 \, km$ in $10 \, minutes$. If it takes $6 \, seconds$ to pass a telegraph post,then the length of the train is (in $meters$):

$A$ train $300 \ m$ long is running with a speed of $54 \ km/h$. In what time will it cross a telephone pole? (in $seconds$)

Two trains start at the same time from Delhi and Mumbai and move towards each other at the rate of $85 \, km/h$ and $65 \, km/h$ respectively. When they meet,it is found that one train has travelled $20 \, km$ more than the other. Find the distance between Delhi and Mumbai (in $km$).

Walking at $3 \, km/h$,Pintu reaches his school $5 \, minutes$ late. If he walks at $4 \, km/h$,he will be $5 \, minutes$ early. The distance of Pintu's school from his house is (in $km$):

Two cars $P$ and $Q$ start at the same time from $A$ and $B$ which are $120 \, km$ apart. If the two cars travel in opposite directions,they meet after $1 \, hour$,and if they travel in the same direction (from $A$ towards $B$),then $P$ meets $Q$ after $6 \, hours$. What is the speed of car $P$ (in $km/hr$)?