1.About in impossible dream

2.Maybe,but Some dreams are impossible to achieve because the universe does not permit them to be achieved, or because they are so vastly beyond our capability the dreamer will never see the dream through to fruition in hir lifetime. But what then do you do? You find dreams that ARE possible!

3.The song talks about following your dreams that seem like they would never be achievable, to do what's right and to be willing to go through hell itself in order to reach your ultimate goal which is referred to as the unreachable star.

4.Yes, because My Ambition in Life Many people have different ambitions in life so the word ambition has many different meanings, depending on whom you ask. Sometimes they are successful and unsuccessful depending upon the nature of the means. To me ambition is a burning desire to achieve goals to succeed in life. It is the dynamic inner force that has led people to become successful.

I don't know what the answer to number 5 is but I hope it helped.