Step-by-step explanation:
import java.util.Scanner; 
public class Student { 
 public static void main(String[ ] args){
 
 
 
 //Enter 5 test scores
 int[ ] marks=enterMark( );
 //calculate average
 double averageScore=calAverage(marks); 
 //calculate grade
          char theGrade=letterGrade(marks);
 //Display average 
 System.out.println("Average: "+ average Score); 
 //Display grade
          System.out.println(" Grade: "+ theGrade);
 
 /** method collects 5 test scores and returns reference*/
 public static int[ ] enterMark( ){
 
 int[ ] arr=new int[5]; 
 //create Scanner object
 Scanner keyboard=new Scanner(System. in);
 int index=0;
 while ( index<arr.length ){
 System. out.print("Enter test "+ (index+1) ); 
 arr[index]=keyboard. nextInt( ); 
 index++; 
 } 
 return arr;
 } 
/**method calculates and returns average*/
 public static double calAverage(int[ ] arr){ 
 double total=0.0; //to hold total
 double average=0.0;//hold average
 for (int count=0; count<arr.length; count++){ 
 
 total+=arr[count]; 
 }
 average=total/arr.length; 
 return average; 
 
 }
/** method calculates and returns grade*/
 public static char letterGrade(double ave){ 
 char grade; //to hold grade
 if (ave >30)
 grade='D';
 if (ave >50)
 grade='C';
 if (ave > 60)
 grade='B'; 
 if (ave > 70)
 grade='A';
 else 
 grade='F'; 
 return grade;
 }
}