4 students did work for me making $5 an hour working 6 hours a day for 12 weeks. 1 student worked for 4 weeks and one student quit after 8 weeks. 2 students worked 12 weeks. What is the total amount for all students?

1 student: 5 * 6 * 4 = ?

1 student: 5 * 6 * 8 = ?
2 students: 5 * 6 * 12 * 2 = ?

Total: ______