Since car is accelerating uniformly that means we it is accelerating at constant rate if you can say that way. To find its acceleration all we have to do is find difference between v1=13 m/s and v2 = 25m/s and divide it by interval that car is taking to accelerate.
a = (v2-v1)/t = 2,4m/s^2
since car is accelerating at constat rate and truck covers same distance as car needs to accelerate from 13 to 25m that means that we can say that in that period truck travelled at cars average speed.
