Suppose the angular separation of two stars is smaller than the angular resolution of your eyes. how will the stars appear to your eyes?

The two stars will look like a single point of light.

Explanation:

When the angular separation is smaller than angular resolution, the eye will not be able to resolve the stars thus they will appear like a point source of light.Angular resolution is one of the limit that our eyes can see. Angular resolution describes how much our eyes can distinguish two things apart which depends on the angle created by the incoming light rays from the two object. A smaller angle, very small angle for light rays to enter the eye thus little or no details for the eye to distinguish.

truck y has a greater velocity than truck x.