In covering a distance of $30 \, km$,Abhay takes $2 \, hours$ more than Sameer. If Abhay doubles his speed,then he would take $1 \, hour$ less than Sameer. Abhay's speed is (in $km/h$):

$A$ car travels the first $39 \, km$ distance in $45 \, minutes$ and the next $25 \, km$ distance in $35 \, minutes$. What is its average speed in $km/h$?

$A$ $75 \, m$ long train is moving at $20 \, km/h$. It will cross a man standing on the platform in (in $sec$):

Heena and Renu are competing in a $100\, m$ race. Initially,Heena runs at twice the speed of Renu for the first $50\, m$. After the $50\, m$ mark,Heena runs at $\frac{1}{4}$ of her initial speed,while Renu continues to run at her original speed. If Renu catches up with Heena at a distance of $N$ meters from the finish line,then $N$ is equal to (in meters).

Flight $A$ usually takes $1 \, \text{hour}$ more than Flight $B$ to travel a distance of $7200 \, \text{km}$. Due to engine trouble,the speed of Flight $B$ decreases by a factor of $\frac{1}{6}$,so it takes $36 \, \text{minutes}$ more than Flight $A$ to complete the same journey. What is the speed of Flight $A$ (in $\text{km/hr}$)?

The diameter of each wheel of a car is $70 \, cm$. If each wheel rotates $400 \, \text{times per minute}$, then the speed of the car (in $km/hr$) is $\left( \text{Take } \pi = \frac{22}{7} \right)$.