Final answer:
The use of a black Sharpie when marking on the back of a mat is not a universal rule. The choice of mark-making tool in art should be based on the specific requirements of the project, including medium, background color, and permanence.
Step-by-step explanation:
The student's question seems to be about the use of a black Sharpie for mark-making in an art context. The statement 'you should use a black sharpie when marking on the back of a mat' doesn't hold true universally. The effectiveness of a black Sharpie, or any other mark-making tool, depends on the specific requirements of the project. When considering the provided reference about the outline of the hat on a horseman being effectively created by black contour lines, it illustrates how simple black marks can suggest a form on a white page. In art, the use of black contour lines can be a powerful method to define shapes and create optical illusions of objects like hats or other subjects. However, the choice of tool should be based on the medium being used, the background color of the material, and the desired permanence of the marks.