Urgent help Needed plz , Student visa refused

Dear all,

My student visa has been refused on 5/9/2014. ECO says that I am not a genuine student based on the reason that I already hold a masters degree then why am i going again for a masters degree and 2nd objection was that I hadn't researched well for my proposed plan of establishing a language school back in my city after completion of the degree.
In my interview i told him clearly that my degree was in English literature whereas I intend to go for Masters in English Language Teaching, both are different as I require teaching skills and for that I need a professional qualification and to answer their 2nd question, I replied that my husband is more interested in me setting up this business , I have done research but upon my return I shall do more research and then we shall establish this school(its understood).
for these two reasons they rejected my visa. Now, I have planned to go for Admin Review. PLEASE advise me should I just answer them in their given form of the objections raised or can I attach a personal statement as well(some body suggested that I should attach).

one more clarification I need is that how much time do they take for admin review these days? and what are they chances in my case?

Plz advise me. I don't have much time left for AR.