public String getStudentGrade(String aNumber){ // begin getStudentGrade method//You will need to loop through the ArrayList dataStore to retrieve the specified Student object for(int i=0;i<data.size();i++) //loop through all of the students in the list { Student aStudent = (Student) data.get(i); //get the student in the i'th position if (aStudent.getPNumber().equals(aNumber)) //is it the student being searched for? { return aStudent.getGrade(); //if so then return it's grade } } return -1; // This will be done if the cat is not found to inform the program}