Online Quiz Exam in PHP

General information for the website: Online Exam Quiz Application
Kind of development: New website from scratch
Description of every page/module: Hello,
This is a project that allows the management to set exam questions and answers(multiple choice answer WITH a single choice). Some question may have diagram to illustrate more explanation. The question will be randomly displayed from database and one question is shown at a time on the interface and upon clicking the next button, it moves to another question and if previous button was clicked it moves back and display the previous question incase the user want to change the answer and the result will be shown after the over all completion of the quiz exam. Note that the quiz has timer that ends the quiz once the time is up. I know this is a common project and if it is already done or anyone has it already, you can mail me or alert me here.

NOTE
This project is expected to be developed in pure HTML, CSS, JQUERY, PHP & MySql. Questions and answers are stored in the database and the application has an admin part where the admin can add, delete or modify questions and answers, set quiz time, set cut-off mark for the score of students and so on.

Thank you
Description of requirements/features: HTML, CSS, JQUERY, PHP & MySQL
Extra notes: