Question

Once upon a time, three rivals got together in a dark wood on an open spot to compose a quarrel by using guns. It was a kind of duel but there were three people in it and therefore it was a truel. There were A, B and C. There were some rules to be followed in the game. The rules of the games were:
-They have to draw the lots to find who will fire first who will be second and who will be third.
– The next rule is that they will start firing on each other unless there is a last person alive.
– Each person will decide on his own about which person he will fire on.
-it is quite clear that A hits and kills in all the shots and it is 100%. Whereas 80% of the shots are hit by B and C hits 50% of the shots he tries to fire. the three persons have their strategies for firing. Nobody is killed by the stray bullet.

Question: who will have the highest chance of surviving in the truel and how much is the chance?