Final answer:
The subject of this question is Business. It asks why some people may earn more money in their jobs, using the example of Jane Green's position as a supervisor. The question is seeking an explanation for the salary differences.
Step-by-step explanation:
The subject of this question is Business. The question is about why someone may be making more money than the person asking the question, and specifically mentions Jane Green's job as the supervisor of a training department. The question is asking for an explanation as to why others may be earning higher salaries than the person asking.