He no longer felt anything, though very faintly he could hear the impact of the club upon his body. But it was no longer his body, it seemed so far away. And then, suddenly, without warning, uttering a cry that was inarticulate and more like the cry of an animal, John Thornton sprang upon the man who wielded the club. Hal was hurled backward, as though struck by a falling tree. Mercedes screamed. Charles looked on wistfully, wiped his watery eyes, but did not get up because of his stiffness.

John Thornton stood over Buck, struggling to control himself, too convulsed with rage to speak.
“If you strike that dog again, I'll kill you,” he at last managed to say in a choking voice.
“It's my dog,” Hal replied, wiping the blood from his mouth as he came back. “Get out of my way, or I'll fix you. I'm going to Dawson.”
Thornton stood between him and Buck, and evinced no intention of getting out of the way. Hal drew his long hunting-knife. Mercedes screamed, cried, laughed, and manifested the chaotic abandonment of hysteria. Thornton rapped Hal's knuckles with the axe-handle, knocking the knife to the ground. He rapped his knuckles again as he tried to pick it up. Then he stooped, picked it up himself, and with two strokes cut Buck's traces.
Hal had no fight left in him. Besides, his hands were full with his sister, or his arms, rather; while Buck was too near dead to be of further use in hauling the sled. A few minutes later they pulled out from the bank and down the river. Buck heard them go and raised his head to see, Pike was leading, Sol-leks was at the wheel, and between were Joe and Teek. They were limping and staggering. Mercedes was riding the loaded sled. Hal guided at the gee-pole, and Charles stumbled along in the rear.

After reading this passage, explain who each of the following characters is
1. who was buck
2. who was John Thornton
3. who was hal
4. who was joe and teek