A wheel's uniform angular acceleration is constant. Initially its angular velocity is zero. During the first 1.0 s time interval, it rotates through an angle of 90.0°.

(a) Through what angle does it rotate during the next 1.0 s time interval?

(b) Through what angle during the third 1.0 s time interval?

I know similar questions have been posted before, but none are very helpful to me, so if one could give me a setup of how to do these please! I thought that for a it would be 180 degrees and for b) 270 degree, but its wrong.