public async Task <Exam> GetExamwithQuestionsWithAnswers(int id)
{
var exam = await ExamRepo.GetAsync(id);
var questions = await QuestionRepo.FindBy(a => a.ExamId == id).ToListAsync();
foreach (var q in questions)
{
q.Answers = await AnswersRepo.FindBy(a => a.QuestionId == q.Id).ToListAsync();
}
return(exam);
}