static class A
    {
        public static void Exc1()
        {
            int a = 10;
            a = a / 0;
        }

        public static void Exc2()
        {
            try
            {
                int a = 10;
                a = a / 0;
            }
            catch(Exception ex)
            {
                throw new Exception("Dzielenie przez 0");
            }
        }

        public static void Exc3()
        {
            try
            {
                int a = 10;
                a = a / 0;
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
    }