$A$ train $700 \, m$ long is running at a speed of $72 \, km/hr$. If it crosses a tunnel in $1 \, minute$,then the length of the tunnel (in $metres$) is:

$A$ $570 \, m$ long train crosses a platform of equal length in $15 \, s$. What is the speed of the train in $m/s$?

$A$ man takes $6$ hours $30$ minutes in walking to a certain place and riding back. He would have gained $2$ hours $10$ minutes by riding both ways. How long would he take to walk both ways? (in minutes)

$A$ man goes from a place $A$ to $B$ at a speed of $12 \, km/h$ and returns from $B$ to $A$ at a speed of $18 \, km/h$. The average speed for the whole journey is? (in $km/h$)

$A$ man walks $6 \, km$ at a speed of $1 \frac{1}{2} \, km/h$,runs $8 \, km$ at a speed of $2 \, km/h$,and travels another $32 \, km$ by bus. The speed of the bus is $8 \, km/h$. Find the average speed of the man in $km/h$.

It takes $8\, hours$ for a $600\, km$ journey,if $120\, km$ is done by train and the rest by car. It takes $20\, minutes$ more,if $200\, km$ is done by train and the rest by car. The ratio of the speed of the train to that of the car is