public class Ex05 { // 계산기. public static void main(String[] args){ Calc calc = new Calc(); long result1 = calc.add(5L,3L); long result2 = calc.substract(5L,3L); long result3 = calc.divide(5L,3L); double result4 = calc.multiple(5L, 3L); System.out.printf("%d %d %d %f",result1, result2, result3, result4); } } class Calc{ long add(long a, long b){ long result = a+b; return result; } long substract..