pluralsight-csharp-fundamentals/gradebook/test/GradeBook.Tests/BookTests.cs

using System;
using Xunit;
using GradeBook;

namespace GradeBook.Tests
{
    public class BookTests
    {
        [Fact]
        public void Test1()
        {
            // arrange
            var book = new Book("");
            book.AddGrade(89.1);
            book.AddGrade(90.5);
            book.AddGrade(77.3);
            
            // act
            book.ShowStaticstics();
        }
    }
}