Your instructor will probably explain the course grading policy on the first day of class. (If not, ask!) If you have a complaint about grading, there is a specific procedure to follow:

First, make an appointment with your instructor. Prepare carefully for this appointment by reworking the problem involved so that you understand it completely. Present your case politely, and be sure to obtain answers to all questions that you have. Usually this meeting will resolve any differences between you and your instructor regarding the grading of your work. If it does not, however, politely leave your instructor's office. You can usually contact the chair of your instructor's department to discuss your situation further.

There is a Grade Appeal Procedure in the Missouri S&T Student Academic Regulations (available by a link on the Registrar's website http://campus.mst.edu/registrar).