1. I think Perseus can slay the gorgon by his own hands because he is a strong and brave man considering the fact that he is Zeus son, he must have inherited a fraction of his powers.
2. I think Andromeda will still react the same way she'd react previously, scared and frightened.
3. Yes, I believe that Perseus ability is a gift because it takes guts and courage to take on a quest that has a higher chance of failing and winning but his determination and courage makes him a hero and a winner.