1.if a body has been rotating about its axis and we place this body on a rough surface so that it decelerates and ultimately attains the state of pure rolling.will the angular momentum remain conserved before and after it attained the state of pure rolling?

2. Q 86, hc verma, rotational motion

3. if the ice at the poles melts and flows towards the equator, how will it affect the duration of day-night?(based on rotational mechanics)