Abishek,
1) All questions are multiple choice. However, you are given a ThingWorx environment, and you must use it to get the correct answer to some of the questions.
2) There are 23 questions on the exam. If you take it more than once, you will not get the same set of questions.
3-4) This is a very difficult exam. I would say a beginner is unlikely to pass, and passing may require some real-world implementation experience.
If you take this exam, I suggest not worrying too much about time. 23 multiple questions in 3 hours is very comfortable from a timing standpoint.
Although it's tough, it is open-note and timing is comfortable, so if you take it, consider keeping the ThingWorx Help Center and references to the source PTCUniversity courses available to you during the exam. You have some time to try and look stuff up during the exam.