Formula use:

v=u+at

Explanation

Given,
Initial Velocity (u) = 45\ km/hr
Acceleration (a) =20\ cm/{sec}^2
Time (t) = 25\ sec
Now , 1st covert the value of initial velocity “km/hr” to “m/sec” .
Initial Velocity (u) = 45\ km/hr
\rightarrow 45\times\large\frac{5}{18}\normalsize\ m/sec
\rightarrow12.5\ m/sec
Acceleration (a) =20\ cm/{sec}^2 or 0.2\ m/s^2 _[100cm=1m]
Now,
v=u+at
\rightarrow v=12.5+\left(0.2\times25\right)
\rightarrow v=12.5+5
\therefore v=17.5\ m/s
So that, its velocity will be 17.5\ m/s after 25 seconds.
Ans: Final velocity (v)\ =\ 17.5\ m/s\ .