Problem:
Susan is trying to decide whether or not to attend college during the next 12-week session. She has the following options:
- Attend college full-time at a cost of $1,200.
- Attend college part-time at a cost of $600 and work part-time earning $1,500.
- Work full-time earning $4,500.
Required:
Question: What is Susan's incremental profit if she chooses option 3 over option 2?
Note: Please describe comprehensively and provide step by step solution.