The average speed of a car is $1 \frac{4}{5}$ times the average speed of a bus. $A$ tractor covers $575 \, km$ in $23 \, hours$. How much distance will the car cover in $4 \, hours$ if the speed of the bus is twice the speed of the tractor? (in $km$)

$A$ man walks from $A$ to $B$ and back in a certain time at the rate of $3.5 \text{ km/h}$. If he had walked from $A$ to $B$ at the rate of $3 \text{ km/h}$ and back from $B$ to $A$ at the rate of $4 \text{ km/h}$,he would have taken $5 \text{ minutes}$ longer. Find the distance between $A$ and $B$ (in $\text{km}$).

By walking at $\frac{3}{4}$ of his usual speed,a man reaches his office $20 \text{ minutes}$ later than usual. His usual time is (in $\text{minutes}$):

$A$ thief is noticed by a policeman from a distance of $200\, m$. The thief starts running and the policeman chases him. The thief and the policeman run at the rate of $10\, km/h$ and $11\, km/h$ respectively. What is the distance between them after $6\, minutes$? (in $m$)

$A$ train takes $18 \, s$ to pass completely through a station $162 \, m$ long and $15 \, s$ through another station $120 \, m$ long. The length of the train (in $m$) is:

The ratio of the speed of a bus to that of a train is $15: 27$. Also,a car covered a distance of $720 \text{ km}$ in $9 \text{ hours}$. The speed of the bus is $\frac{3}{4}$ the speed of the car. How much distance will the train cover in $7 \text{ hours}$? (in $\text{km}$)