It's strange that you have both of these questions on the same paper.
I've got a question for 10 marks that says "The adversary trial is faultless and cannot be improved, discuss this statement and indicate to to the extent to which your agree?"
As you said, you will want to discuss strengths and weaknesses. I was going to say mention reforms, but your next question kinda covers it...
then on the same paper i have a question for 8 marks thats says "the adversary is not perfect and could be improved" discuss wheather you agree and list two possible improvements"?
Yep here you're agreeing by stating weaknesses and discussing several reforms that can enhance the effectiveness of the adversary system. The textbook Justice and Outcomes has a sub-chapter on reforms.
and also another question im having problems with is for 10 marks "The adversary trial been used for criminal cases provides for a effective legal ssytem discuss if you agree and include 2 elements of a effective legal system"?
Effective legal system =
1: Entitlement to a fair and unbiased hearing
2: Effective access to the legal system
3: Timely resolution of disputes
So here we are agreeing with the question and out of the three elements above, select two. The key words in this question are "criminal cases". I would be discussing committal hearings and how direct indictment speeds up cases (for a timely resolution). You can also say that the purpose of a committal hearing speeds things up (since the process determines if the case is a prima facie case, that is, whether the evidence is sufficient to support a conviction by jury at trial).