Answer:
Question 2:
had...had been going
=》 Past tense will be used as the situation took place a month ago.
Question 3:
True
=》The full question is not given as the last part got cropped out but yes, fixed sentence structure is important in formal english.
Question 4:
I have been cooking.
=》Again, some part of the question has been cropped out but with the given information & assuming that 'almost will be ready soon' or something like comes next in the sentence, the above option seems to be the most accurate one. Otherwise, I cooked will be correct.
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Hope it helps ⚜
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