61.
package com.company;
import java.util.*;
import java.lang.*;

public class ExamScores {
    public static void main(String[] args)
    {
        Scanner input = new Scanner(System.in);
        int min = 100;
        int max = 0;
        int avg;
        int gradeSum = 0;
        System.out.println("Please type 10 of your grades.");
        int grade = input.nextInt();
        int counter = 1;
        gradeSum += grade;
        while(counter <= 10) {
            if (grade < 0 || grade > 100) {
                System.out.println("This grade is invalid");
                counter = 13;
            } else {
                if (grade < min) {
                    min = grade;
                }
                if (grade > max) {
                    max = grade;
                }
                if (counter != 10) {
                    System.out.println("Please type another one of your grades.");
                    grade = input.nextInt();


                    gradeSum += grade;
                }
                counter++;
            }
        }
        avg = gradeSum/10;
        if(counter == 11) {
            System.out.println("The smallest number that you typed is " + min);
            System.out.println("The largest number that you typed is " + max);
            System.out.println("The average of the numbers is " + avg);
        }
    }
}



63.
package com.company;
import java.util.*;
import java.lang.*;

public class IDentifier {
    public static void main(String[] args)
    {
        Scanner input = new Scanner(System.in);
        System.out.println("Type in your ID");
        String id = input.next();
        int length = id.length();
        int counter = 0;
        int digitCounter = 0;
        char currentChar = id.charAt(counter);
        while(counter < length-1){
        if( currentChar == '1'||currentChar == '2'||currentChar == '3'||currentChar == '4'||currentChar == '5'||currentChar =='6'||currentChar == '7'||currentChar == '8'||currentChar == '9'||currentChar == '0'){
                digitCounter++;
            }
            counter++;
            currentChar = id.charAt(counter);
        }
        if(digitCounter == 2){
            System.out.println("The id is valid");
        }
        else{
            System.out.println("The id is invalid");
        }
    }
}




65.
package com.company;
import java.util.*;
import java.lang.*;

public class BinaryToDecimal {
    public static void main(String[] args)
    {
        Scanner input = new Scanner(System.in);
        System.out.println("Type in a binary number");
        String binaryNum = input.next();
        System.out.println("The binary form is: "+Integer.parseInt(binaryNum,2));
    }
}



67.
package com.company;
import java.util.*;
import java.lang.*;

public class PalindromeChecker {
    public static void main(String[] args)
    {
        Scanner input = new Scanner(System.in);
        System.out.println("Type in a sentence");
        String word = input.nextLine();
        String trueWord = word.toLowerCase();
        int length = trueWord.length();
        int counter1 = 0;
        int truthChecker = 1;
        char currentLetter1 = trueWord.charAt(counter1);
        for(int i = 1; i < length; i++){
            if(currentLetter1 == trueWord.charAt(length-i)){
                counter1++;
                currentLetter1 = trueWord.charAt(counter1);
                truthChecker++;
            }

        }
        if(truthChecker==length){
            System.out.println("This is a palindrome");
        }
        else
        {
            System.out.println("Not a palindrome");
        }
    }
}