Such written questions are, in general, protected by copyright, and you cannot reproduce them word-for-word unless you have permission, or some other legitimate basis. Nor can you reproduce them in a close paraphrase, with just a few words changed. That is still an infringement of copyright.
If you are in the US (you don't indicate your jurisdiction, and it makes a difference) such use might be defensible as fair use. Fair use is described in some detail in this question and its answer. Whether copying counts as fair use depends very much on the exact details of the situation, and a general question can never give an answer that can be depended on. That your planned use would be for instruction tends to support the case for fair use. If it is the case that it would not harm the market for the original, that would also tend to support the case for fair use. That the original was factual rather than imaginative or dramatic also inclines a bit towards fair use. If your use is for profit that tends to incline against fair use.
If you are not in the US, there is a somewhat similar concept called "fair dealing" in the UK and Europe. The rules for that are significantly different, and it tends to be less inclusive, as I understand it.
Why not consider reworking the questions, using the ideas from your sources, but not copying word for word, or even in a very close paraphrase? That would be much less likely to infringe copyright, and expose you to a lawsuit.
If you are in doubt, you would be wise to consult a lawyer knowledgeable about copyright. You could describe in detail your plans, and get advice you could better depend on.