Good question.
T-1 usually have all numericals, usually taken from the corresponding course prescribed textbooks. Some numbers might be changed here and there, though. For example, in thermodynamics, if textbook problem has say boiler capacity as 50 m^3, T-1 will have it as 100 m^3. (My first T-1 was 7 years ago. So I have a hard time remembering questions.)
The question paper will have 2-3 questions, each 25 marks, mostly containing numericals. So, if you have gone through the textbook examples, T-1 is a piece of cake. Else, good luck scoring at least average!
Now coming to the preparation part. First thing attend classes. 90% of the things will get easier. Before exam, go through the slides and textbook examples. And practice problems yourself.
This should help you get good marks and secure at least a B grade (for easy courses) and C grade (for tough courses