Hector works 10 hours per week at a part-time job. His original pay rate was $8.50 per hour, but he recently received a raise of x dollars per hour. His new total weekly pay, y, is represented by the equation y = 10(8.5 + x). If Hector earned $100 last week, what was the amount of Hector's raise per hour? A . $12.00 B .$15.00 C. $1.50 D. $3.00