Answer:
No, Morris did not infringe McMahon's copyright
Explanation:
Style of writing a textbook is a general feature or guideline and not copyrightable. This implies that, Morris could write a book in a similar styles like the ones used by McMahon in his psychology text book. However, since the content of the book is not the same as McMahon's book, which could be termed as plagiarism, therefore, Morris did not infringe McMahon's copyright.