To determine how many hours you will need to work at the new job before your investment in education has "paid off," you can use the following calculation:
Let "x" be the number of hours you need to work.
With the new job, you earn $2 more per hour, so you earn $2x more for every hour worked. However, you also have to account for the initial cost of the course, which is $500.
So, you want to find the point where the additional earnings cover the course cost:
$2x - $500 = 0
Now, solve for x:
$2x = $500
x = $500 / $2
x = 250 hours
Therefore, you will need to work 250 hours at the new job before your investment in education has "paid off." So, the correct answer is option (d).