There are a lot of questions to answer. Is it necessary to answer in sequence and how to manage the time so that I can answer each of the question with a minimum perfection?
It iS NOT necessary to answer in sequence. Just make sure that you write the question number at the start of your answer ( start each answer on a separate page )
Use the 15 minutes reading time effectively – read the exam technique article on this site – and spend no more than 18 minutes on each question / answer once the invigilator has said ” you may now start”