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Many instructors prefer this method of grading to dissuade students from answering a question without giving it proper consideration, or outright by guessing. However, we realize how frustrating it can be to be honestly working through a problem and find that each time you re-try a question a negative score builds up. In these cases, we highly recommend attending office hours, or seeking a study group to help check each other's work, in order to give each attempt the best possible chance of being correct.
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