Hi LmessiA,
I just looked at your track record.
You have been answered on 3 previous threads.
You have only ever said thank you once for an answer.
You do not give point credit to your answerers.
You have never commented in any other way, other than that one thank you.
If you want answers to explain in more detail then you need to interact with them.
I am letting you know that your manners and attitude are under watch.
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Having said all that negative stuff I will also add that it is good that you gave your answer of 30%.
It is good to see that people have tried to answer questions for themselves
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Yes 12/40 is 30% so this does seems a reasonable estimate based on the very limited fact that you have been given.