I'm new here, so I apologize if this is the wrong place to ask this question.
I'm a student, and I have a 4-page PDF document of a sample test. The answers to the test questions are written on the document in blue pen; the only other colors in the document are black (the text questions) and white (the PDF background).
Is there a free, easy way to remove all instances of blue from the document? I thought something in Photoshop might work, but I unfortunately don't have access to any image editing software right now.