Choices 'C' and 'D' are both correct.
(Except in 'C', changing the temperature from 1°C to 3°C is not usually
described as 'cooling', and it's not the water's 'mass' that changes. But
water does contract in volume during that change.)
Acceleration = Change in Velocity / time
a = (v - u) / t
Where v = final velocity in m/s
u = initial velocity in m/s
t = time in seconds.
a = acceleration in m/s²
A proper record of the changes in velocity with the corresponding time would help find the acceleration.
It is D as u dont need a stop watch aft that
If you only know its speed, that's not enough information to catch it. You could even chase it at DOUBLE that speed, and you'd never catch it if you were chasing in the wrong direction.
You also have to know the DIRECTION the runaway car is going, so that you can chase in the same direction.
Now that you know its speed AND direction, you know its velocity. You need that information to have any chance of catching it.
