A student of yours gets a part-time job at the library that pays $7.50 per hour. Which of the following expressions represents the final math operation you would perform in figuring out her total earnings if she works 3 hours on Monday, 6 hours on Tuesday, 2 hours on Wednesday, 3 hours on Thursday, and 4 hours on Friday?
A. 3+6+2+3+4 B. 18+ $7.50 c. 18($7.50) D. 5($7.50)​