interface IClientTest
        {
            bool Test(Client client);
            void Report(Client client);
        }
        
        
        class CoefficientTest : IClientTest
        {
            readonly double income, years, min;
            public CoefficientTest(double income, double years, double min)
            {
                this.income = income; this.years = years; this.min = min;
            }
            public void PrintInfo()
            {
                Console.WriteLine("income*{0}+years*{1} >= {2}", income, years, min);
            }
            bool IClientTest.Test(Client cl)
            {
                return cl.Income * qIncome + cl.YearsInJob * qYrs < min;
            }
            void IClientTest.Report(Client cl)
            {
                Console.WriteLine("Coefficient {0} is less than {1}.",
                cl.Income * income + cl.YearsInJob * years, min);
            }
        }

test is  IClientTest

test is  IClientTest