Advantage Adjustable 11-Inch Hitch Extension

does this reduce down to an 1-1/4" to fit a bike rack?

Can you use a locking mechanism on this extension to prvent theft?

Is a specific hitch cover made for this extender? Std covers have hole 2 1/2" from end. This has hole 2" from end.

Can you tell me the distance to the center of the first receiver hole from the back edge? Looks like it might be 1 inch to maybe 1 1/2 inches. Thank