$A$ man can row three-quarters of a kilometre against the stream in $11 \frac{1}{4}$ minutes. The speed (in $km/hr$) of the man in still water is

$A$ sailor goes $12$ $km$ downstream in $48$ $min$ and returns in $1$ $h$ $20$ $min.$ The speed of the sailor in still water is..........$km/h$.

$A$ man can row $44 \text{ km}$ downstream in $4 \text{ hours}$. If the man's rowing rate in still water is $8 \text{ km/hr}$,then find in what time will he cover $25 \text{ km}$ upstream? (in $\text{hours}$)

The current of a stream runs at $1 \, km/h$. $A$ motor boat goes $35 \, km$ upstream and back again to the starting point in $12 \, hours$. The speed of the motor boat in still water in $km/h$ is:

$A$ man can row $6\, km/h$ in still water. If the river is running at $2\, km/h$,it takes $3\, hours$ more to row upstream than to row downstream for the same distance. How far is the place? (in $km$)

Keshav can row $60 \ km$ downstream and $36 \ km$ upstream,taking $10 \ h$ each time. What is the velocity of the current? (in $km/h$)