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.