Which is more correct:

This rule specifies that an object should be either visible or invisible, but not partially visible.

Or

This rule specifies that an object should either be visible or invisible, but not partially visible.

Is there any rule for that?

Also, should the be be repeated after the or in the second statement?

Which is more correct:

This rule specifies that an object should be either visible or invisible, but not partially visible.

Or

This rule specifies that an object should either be visible or invisible, but not partially visible.

Is there any rule for that?

Also, should the be be repeated after the or in the second statement?

Which is more correct:

This rule specifies that an object should be either visible or invisible, but not partially visible.

Or

This rule specifies that an object should either be invisible or invisible, but not partially visible.

Is there any rule for that?

Also, should the be be repeated after the or in the second statement?

Which is more correct:

This rule specifies that an object should be either visible or invisible, but not partially visible.

Or

This rule specifies that an object should either be visible or invisible, but not partially visible.

Is there any rule for that?

Also, should the be be repeated after the or in the second statement?