$A$ train running at $\frac{7}{11}$ of its normal speed reached a place in $22\, \text{hours}$. How much time could be saved if the train had run at its normal speed? (in $\text{hours}$)

Sound travels $330 \text{ m/s}$. If the sound of a thundercloud is heard $10 \text{ s}$ after the flash,the distance of the thundercloud is (in $\text{km}$):

$A$ 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 $km/h$?

Raj and Prem walk in opposite directions at the rate of $3 \, km/h$ and $2 \, km/h$ respectively. How far will they be from each other after $2 \, hours$? (in $km$)

$A$ thief is spotted by a policeman from a distance of $400\, m$. When the policeman starts the chase,the thief also starts running. Assuming the speed of the thief is $5\, km/h$ and that of the policeman is $9\, km/h$,how far will the thief have run before he is overtaken by the policeman? (in $m$)

$A$ student walks from his house at a speed of $2 \, km/h$ and reaches his school $6 \, minutes$ late. The next day,he increases his speed by $1 \, km/h$ and reaches $6 \, minutes$ before school time. How far is the school from his house? (in $km$)