$A$ train travels at a speed of $10\, m/s$ and leaves Trivandrum for Nagercoil at $8\, AM$. At what distance from Nagercoil will it meet a train which leaves Nagercoil for Trivandrum at $8.20\, AM$ and travels one-third faster than the former? The distance from Trivandrum to Nagercoil is $68\, km$. (in $km$)

Two trains measuring $100\, m$ and $80\, m$ respectively,run on parallel tracks. When travelling in opposite directions,they are observed to pass each other in $9\, s$. When they are running in the same direction at the same speeds as before,the faster train passes the other in $18\, s$. Find the speeds of the two trains in $km/h$.

How long will a boy take to run round a square field of side $35 \, m$,if he runs at the rate of $9 \, km/hr$ (in $sec$)?

$A$ train $150 \, m$ long is running at $95 \, km/h$. How much time will it take to pass a man moving in the same direction at $5 \, km/h$? (in $seconds$)

The distance of the sun from the earth is $143,400,000 \text{ km}$. Light travels from the sun to the earth in $7 \text{ minutes}$ and $58 \text{ seconds}$. The velocity of light per second is (in $\times 10^5 \text{ km/sec}$):

With a uniform speed,a car covers a certain distance in $8 \, hours$. Had the speed been increased by $4 \, km/hr$,the same distance could have been covered in $7.5 \, hours$. What is the distance covered? (in $km$)