Mark 5 study questions

Why does Jesus make the pigs run down the hill into the sea? (v 12 and 13)

There seems to be connection between the miracle of Legion and Isaiah 65. Why?

What is the significance of the 12 years that occurs twice in this chapter? Are we supposed to make any spiritual connections or these just coincidental facts? (v 25 and v 42)

What does it mean for power to go out of Jesus?