t = 2s,
u = 30 km h-1 or 8.33 m s-1
v = 33.6 km h-1 or 9.33 ms-1
acceleration (a) = v - u\over t
or, a = 9.33 - 8.33\over 2
or, a = 1\over 2 = 0.5 ms-2
For the next 2 s,
u = 9.33 m s-1
v = 37.2 km h-1 or 10.33 ms-1
a = 10.33 - 9.33\over2 = 0.5 m s -2
Yes, the acceleration is uniform as the acceleration in both instances is same.