For the first question, I'd definitely elaborate more on the social purpose - what you have listed sounds too similar to the function of the text: to inform. Perhaps you may want to write: the social purpose of the referential written text is to guide readers in the process of nominating an eligible Australian citizen to be placed under consideration for an Order of Australia award, a title of virtue governed by the Australian honours system. With the interrogatives, I think you should explicitly state that it fulfils the social purpose by guiding nominators to the answers they may need in order complete a nomination. Finally, you should make reference to the final subheading, which in fact isn't an interrogative... (it's a declarative).
For the second question, your explanations are slightly weak - I would say that the use of elevated lexis, which are derived from French OR Latin origin (pick one which is correct, otherwise don't mention it), are used to reinforce the authority of the Australian Honours System, thereby contributing to the text's formality. With your second piece of evidence, I would highly suggest that you refrain from mentioning what's lacking in the text; focus on what's present. So instead of talking about the lack of contractions (not sure how these allow for precise communication...)., I'd talk about the use of jargon and how that allows the government body to exercise their expertise on the text's field, thereby increasing the formality of the text.
For the third question, you have listed two different features which fall under the branch of formatting - depending on the teacher marking this piece, you may get half the marks as they may see this as addressing one coherency feature. To be safe, I'd replace one that you have for another coherency feature, such as logical ordering. Also, I feel as though there are a few punctuation errors in your response (may just be me since I'm quite pedantic on those minor things

). My response: The utilisation of subheadings, such as in line 54; "Who can be nominated", allows the readers of the written text to efficiently select the question they may attain regarding nominations for the Order of Australia award. As a result, this formatting provides a sense of clarity for the readers, thereby contributing to the overall coherence of the text. Furthermore, the logical ordering of the text aids with its coherence as it lists the information in a systematic manner, whereby potential nominators are able to best extract relevant information; the article begins with an introduction, detailing the role of the Australian Honours System, then continues by listing and explaining the different categories of the Order of Australia awards, subsequently following a question-answer structure to guide the readers to their question, finally ending with contact details if the readers still obtain unanswered questions.
The fourth question is well answered, just a few tips to improve: add quotes in your response since it's 3 marks, and instead of saying that the passive voice adds 'complexity', I'd say it adds an authoritative tone. Also, you could perhaps link this to reinforcing hierarchical structures, whereby the power and prestige of the government body is emphasised by making a direct mention to the reader (inclusive language), thereby widening the social distance and thus increasing the formality. Also, mention it's an agentless passive instead of just passive.
For the fifth question, I presume 1 mark comes from quoting the use of active voice, and the other mark comes from linking it to the social purpose. The active voice provides a clear indication of the initiator and the target of an action, as the agent and patient are matched with the subject and object respectively. Therefore, this supports the social purpose by guiding the audience - potential nominators - through the process of making and submitting a nomination in an efficient manner. Just chuck a nice quote in there and it should be good. Maybe you might want to make a reference to the fact that active places emphasis on the subject.
For the final question, I'm not sure if your example of parallelism is correct. I'd put something like "any individual, community organisation, ...an award" (56-58) as listing is a form of parallelism. Apart from that, everything is fine.
Hope that helped