Jamal works part-time earning $8,000 per year. He reduces his work hours by half so that he can go to school. Jamal completes his degree after 3 semesters (1.5 years) at a cost of $1,400 per semester in tuition and $500 per semester in books. What was Jamal's investment in getting his degree?
a.

$4,700
b.

$5,700
c.

$11,700
d.

$17,700