Increasing the distance increases the rotational inertia, making it harder to change the object's rotational motion.

The rotational inertia increases. This is described by the parallel axis theorem.

Pulling their arms in decreases the distance of their mass from the axis of rotation, decreasing their rotational inertia and increasing their angular speed.

Calculate the rotational inertia ($I = mr^2$) for each object and then sum them: $I_{tot} = \sum I = \sum mr^2$.

1. Identify $I_{cm}$ (inertia about the center of mass). 2. Determine 'd' (distance between the parallel axis and the center of mass axis). 3. Calculate $I' = I_{cm} + Md^2$.

Increases the rotational inertia.

Increases the rotational inertia.

The rotational inertia is minimized.

The object will experience a smaller angular acceleration.

The rotational inertia increases, as described by the parallel axis theorem.