big start on QuizStatus

app/models/candidate.rb

@@ -1,4 +1,6 @@
 class Candidate < ApplicationRecord
+  belongs_to :quiz
+  has_many :questions, through: :quiz
   has_many :answers
   belongs_to :recruiter, class_name: "User"
 
@@ -8,6 +10,14 @@ class Candidate < ApplicationRecord
   validates_presence_of :test_hash
   validates_uniqueness_of :test_hash
 
+  def submitted_answers
+    answers.where(submitted: true)
+  end
+
+  def answered_questions
+    answers.where.not(answer: nil)
+  end
+
   private
 
     def generate_test_hash

app/models/quiz.rb

@@ -1,3 +1,4 @@
 class Quiz < ApplicationRecord
   has_many :questions
+  has_many :candidates
 end