You are required to write a minimum of 150-225 words in the first task and 300-350 in the second.
I suggest you to write more words than that, I would say 250-300 for the first and 350-400 for the second.
However, do that only if you have plenty of time to review it and if it doesn't affect the quality of your essay. I think it's far more important to have 5 minutes to review and to improve the structure of the essay, than adding words.
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