changed the access modificators and wrote the tests for my case

src/methods.cs

@@ -2,31 +2,33 @@ namespace struct_lab_student
 {
 	public partial class Program
 	{
-		static void Var9(List<Student> students) 
+		public static void Var9(List<Student> students)
 		{
 			WriteData(ProcessData(students), "../data_new.txt");
 			Console.WriteLine("\nДані збережено у data_new.txt");
 		}
 
-		static void Var10(List<Student> students)
+		public static void Var10(List<Student> students)
 		{
 			Console.WriteLine("\nСписок студентів з відмінними оцінками з фізики:");
 			foreach (var student in Filter(students, IsTalentedPhysician))
 				Console.WriteLine($"{student.surName} {student.firstName} {student.patronymic} {EvalAverage(student):0.0} {student.scholarship}");
 		}
 
-		static void Var24(List<Student> students)
+
+		public static void Var24(List<Student> students)
 		{
 			Console.WriteLine("\nСписок студентів, які народились влітку:");
 			var summer_kids = Filter(students, IsSummer);
 			foreach (var dude in summer_kids)
-				Console.WriteLine($"{dude.surName} {dude.firstName} {EvalAverage(dude):0.0}");
+
+				Console.WriteLine($"\r{dude.surName} {dude.firstName} {EvalAverage(dude):0.0}");
 		}
 
-		static List<Student> ProcessData(List<Student> students)
+		private static List<Student> ProcessData(List<Student> students)
 		{
 			List<Student> processedStudents = [];
-
+      
 			foreach (var student in students)
 			{
 				var newStudent = student;
@@ -37,13 +39,14 @@ static List<Student> ProcessData(List<Student> students)
 			return processedStudents;
 		}
 
-		static void WriteData(List<Student> students, string filename)
+		private static void WriteData(List<Student> students, string filename)
 		{
-			var max_len = students.Max(s=>s.surName.Length);
-			using (StreamWriter writer = new(filename)) {
+			var max_len = students.Max(s => s.surName.Length);
+			using (StreamWriter writer = new(filename))
+			{
 				foreach (var student in students)
 				{
-					writer.WriteLine($"{student.surName.PadRight(max_len+2)} {student.firstName.PadRight(max_len+2)} {student.patronymic.PadRight(max_len+2)} " +
+					writer.WriteLine($"{student.surName.PadRight(max_len + 2)} {student.firstName.PadRight(max_len + 2)} {student.patronymic.PadRight(max_len + 2)} " +
 									$"{student.sex,-3} {student.dateOfBirth,-12} {student.Marks[0],-3} {student.Marks[1],-3} {student.Marks[2],-3} " +
 									$"{student.scholarship}");
 				}
@@ -55,13 +58,13 @@ public static IEnumerable<Student> Filter(List<Student> students, Func<Student,
 			return students.Where(Condition);
 		}
 
-		private static bool IsSummer(Student student)
+		public static bool IsSummer(Student student)
 		{
 			int month = int.Parse(student.dateOfBirth[3..5]);
 			return month >= 6 && month <= 8;
 		}
 
-		private static bool IsTalentedPhysician(Student student)
+		public static bool IsTalentedPhysician(Student student)
 		{
 			return student.Marks[1] == '5';
 		}

tests/runTest.bash

@@ -0,0 +1 @@
+dotnet build ./src/src.sln  && dotnet build ./tests/ && dotnet test --no-build --verbosity normal ./tests

tests/tests.cs

@@ -1,15 +1,44 @@
 using Xunit;
 using struct_lab_student;
 
-namespace student_tests {
-	public partial class Tests {
+namespace student_tests
+{
+	public partial class Tests
+	{
 		[Fact]
-		public static void Student_Constructor_ReturnStudentList() {
+		public static void Student_Constructor_ReturnStudentList()
+		{
 			List<Student> students = [];
 			students.Add(new("Прізвище1 Ім'я1 По-батькові1 M 02.02.2000 3 4 5 1234"));
 			students.Add(new("surname FIRST_NAME 🔥 F 02.02.2000 4 - 2 1234"));
 			students.Add(new("1 2 3 4 5 - - - 6"));
 			Console.WriteLine(students.Count < 3 ? "this is a test, stupid" : "no way!");
 		}
+
+		[Fact]
+		public static void TestVar10()
+		{
+			List<Student> students = [];
+			students.Add(new("Андрущенко Вадим Миколайович M 23.06.2004 2 1 - 1285"));
+			students.Add(new("Стакан Єгор Олександрович Ч 04.01.2006 4 5 3 4319"));
+			students.Add(new("Кірпіч Влад Шварцович Ч 12.06.1998 4 4 5 3538"));
+			students.Add(new("Муха Саня Респектович F 12.11.1999 3 5 4 3392"));
+
+			int count = 0;
+			foreach (Student student in students)
+			{
+				if (Program.IsTalentedPhysician(student))
+					count++;
+			}
+			Assert.Equal(2, count);
+
+			double[] expectedAverages = { 1.7, 4.0, 4.3, 4.0 };
+			int counter = 0;
+			foreach (var student in students)
+			{
+				Assert.Equal(Program.EvalAverage(student), expectedAverages[counter]);
+				counter++;
+			}
+		}
 	}
-}
+}