doesn't really matter -- you will never have to deal with this issue, one way or the other, on an official problem.
no way.
the problems will almost certainly say something like "positive prime number", making it explicit. if they don't, then there will be some other context that implies or requires the primes in question to be positive.
Ron has been teaching various standardized tests for 20 years.
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Pueden hacerle preguntas a Ron en castellano
Potete chiedere domande a Ron in italiano
On peut poser des questions à Ron en français
Voit esittää kysymyksiä Ron:lle myös suomeksi
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Quand on se sent bien dans un vêtement, tout peut arriver. Un bon vêtement, c'est un passeport pour le bonheur.
Yves Saint-Laurent
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