Horses are faster at short distances than camels, but they can travel much further distances.

Who is "they" in this prior sentence?
camels
The judges monitor the performance of the competitors to measure their abilities, but they do not decide if they move on to the next round.

Who is "they" in this prior sentence?
The judges
Randy went to Nick's store, and bought his groceries.

Who is "his" in this prior sentence?
Randy