1. I think that work is really essential to have a happy and successful life. First of all, it brings you money, which is necessary just for living. Secondly, if you satisfied in what you are doing, the job can become the meaning of all you life. So, work is essential, especially nowadays.
2. I would ask that person, was it his/her decision, to choose these kind of job, or was he given some piece of advice. If it was his/her decision, I would ask, when he/she realized it, and if it was some advice, who recommended it.
3. During the holidays every teenager can earn money. How? They can give out booklets with advertisement, wash cars, sit with babies, be tutors for little children and so on. It depends on teen's desire and his/her possibilities.
4. I think it's fifty-fifty. I can't choose only one thing. It should be combined, because if you don't like your job, it won't bring you satisfaction. But if it doesn't bring you good money, you also won't be satisfied. So I think that person should try to combine his/her wish to work in this or that sphere, and salary, money, that he/she would get from doing this work.