public String GradeStudent(String StudentId, int HomeworkId, int week, float grade, string feedback) { try { Student s = StudentRepo.FindOne(StudentId); if (s == null) { return("Student not found."); } Homework h = HomeworkRepo.FindOne(HomeworkId); if (h == null) { return("Homework not found."); } float finalGrade = h.ComputeGrade(grade, week); GradeRepo.Save(new Grade(StudentId, HomeworkId, week, finalGrade, feedback)); return("Student graded " + finalGrade + "."); } catch (Exception e) { return(e.Message); } }