Give important factor to control the speed of vehicle in area of school or hospital.

Mark the correct statements for a particle going on a straight line

A particle starts from rest at $x=0\; m$ with an acceleration of $1 \,m / s ^2$. At $t = 5\;s _{ s }$ it receives an additional acceleration in the same direction as its motion. At $t =10\; s$ its speed and position are $v$ and $x$, respectively. Had the additional acceleration not been provided, its speed and position would have been $v _0$ and $x _0$, respectively. It is found that $x - x _0$ is $12.5 \,m$. Then one can conclude that $v - v _0$ is .............. $\,m / s$

A car, moving with a speed of $50 \,km/hr$, can be stopped by brakes after at least $6\,m$. If the same car is moving at a speed of $100 \,km/hr$, the minimum stopping distance is..........$m$

A car, starting from rest, accelerates at the rate $f$ through a distance $S$, then continues at constant speed for time $t$ and then decelerates at the rate $\frac{f}{2}$ to come to rest. If the total distance traversed is $15S$, then

The velocity of a particle moving in the positive direction of $x$-axis varies as $v=5 \sqrt{x}$. Assuming that at $t=0$, particle was at $x=0$. What is the acceleration of the particle $.........m/s^2$