static void Main(string[] args)
{
// List<double> grades = new List<double>();
var book = new Book("Paul's Grade Book");
book.AddGrade(89.1);
book.AddGrade(90.1);
book.AddGrade(900.1);
Book.Generation();
var stats = book.GetStatistics();
Console.WriteLine($"The lowest grade is {stats.Low}");
Console.WriteLine($"The highest grade is { stats.High }");
Console.WriteLine($"The average grade is {stats.Average:N1}");
}
