live-test-answer-sheet

answer.cs

// Answer 1:
var answer1 = from s in students
              where s.Age > 20
              select s;

foreach (var student in answer1)
{
    Console.WriteLine($"Name: {student.Name} | Age: {student.Age}");
}

// Answer 2:
var answer2 = from c in courses
              orderby c.Credits descending
              select c;

foreach (var c in answer2)
{
    Console.WriteLine($"Name: {c.CourseName} | Age: {c.Credits}");
}

// Answer 3:

var answer3 = from s in students
              group s by s.Department into g
              select new
              {
                  Department = g.Key,
                  StudentCount = g.Count()
              };

foreach (var s in answer3)
{
    Console.WriteLine($"Name: {s.Department} | Number of student: {s.StudentCount}");
}


// Answer 4:

var answer4 = from s in students
              join e in enrollments
                  on s.Id equals e.StudentId
              join c in courses
                  on e.CourseId equals c.CourseId
              where c.CourseName == "Data Structures"
              select new
              {
                  StudentName = s.Name,
                  e.Grade
              };

foreach (var q in answer4)
{
    Console.WriteLine($"Name: {q.StudentName} | Grade: {q.Grade}");
}



// Answer 5:
var answer5 = from s in students
              where s.Department == "Computer Science"
              where s.GPA > 3.5
              select s.GPA;


var avg = answer5.Average();

Console.WriteLine($"average: {avg}");