Answer:
CLS
INPUT"Enter any three numbers";a,b,c
IF a>b AND a>c THEN
PRINT a;"is the greatest"
ELSEIF b>a AND b>c THEN
PRINT b;"is the greatest"
ELSE 
PRINT c;"is the greatest"
ENDIF
END
 
        
             
        
        
        
Answer:
the software that manages and controls the activities and resources of the computer is OS
Explanation:
the software that manages and controls the activities and resources of the computer is OS
because here we know that CPU is hardware 
and ALU is a digital circuit that is use to perform arithmetic and logic operations
and 
GUI or Graphical User Interface controls the graphical interface of the applications
so here correct option is OS that is the software that manages and controls the activities and resources of the computer
 
        
             
        
        
        
Answer:
import java.util.Scanner;
class Main {  
  public static void main(String args[]) { 
        Scanner scan = new Scanner(System.in);
        System.out.print("Enter a decimal value (0 to 15): ");
        int num = scan.nextInt();
        scan.close();
        
        if (num < 0 || num >15) {
            System.out.printf("%d is an invalid input\n", num);
        } else {
            System.out.printf("The hex value is %X\n", num);
        }
  } 
}
Explanation:
Hopefully this example will get you going for the other assignments.