Which has a greater velocity?

a ball rolling down a 3.4m hill in 8.5s or a fish swimming upstream, covering 6.2m in 0.6 minutes? (velocity = change in distance / change in time)

they have the same velocity
the fish
the ball
they can't compare because they have different time units

Two steel balls, each of mass m, are welded to a light rod of length l and negligible mass and are initially at rest on a smooth horizontal surface. a horizontal force of magnitude f is suddenly applied to the rod as shown. determine (a) the instantaneous acceleration a of the mass center g and (b) the corresponding rate at which the angular velocity of the assembly about g is changing with time.