A professor has collected his student's test marks. Your program can read the marks until the sentinel value -1 is entered by the user. Write a program to check and display the number of students, the average of mark, and the highest marks of the student. (10 marks) A professor has collected his student's test marks. Your program can read the marks until the sentinel value -1 is entered by the user. Write a program to check and display the number of students, the average of mark, and the highest marks of the student. (10 marks)