Question: And the labor-market success of millions of unskilled immigrants in recent years makes it hard to sustain the case that only highly trained or educated workers are in demand--at least for the moment.
Unskilled laborers have gained jobs in the food service industry.

Answer: it is not possible to tell

Question: Amidst all this, Jack Lord and his hair died.
Jack died amidst it all.

Answer: yes

Question: Supposedly it sits on the site of the Dubh Linn (Black Pool) that gave Dublin its name.
Dublin is located next to the Black Pool (Dubh Lin), hence its name.

Answer:
it is not possible to tell