Are notes/comments that are entered into student agraphics viewable by students?

No. The notes field are visible only by the Secretariat and to Lecturers who have active Courses with the Student.

The Teacher can view the notes by clicking on a Student's Name in the Students enrolled of the Course and navigating to the relevant tab "Comments/Notes."

The inclusion of the Notes/Comments Is by Default active only for the Secretariat. It can be enabled for Teachers in Configuration → Settings → Settings related to Teachers the entry "Teacher can add private notes to student profile."