Do not write as though your reader had a copy of the problem statement available. Introduce all parts of the problem and define all symbols as part of your solution. If in my opinion even a couple of sentences from one student's work are copied to another, both problems will receive no credit. You should form study groups to work on the problems together, but you learn by writing in this course so your answers must finally be your own words. I will have more to say about mathematical writing as the semester progresses.
Wrong answers receive no credit.
Wrong answers are less valuable than no answer. If you haven't got an answer, there is always hope you will get one. Once you have accepted a wrong answer from yourself, you have eliminated the possibility of getting the problem right. You are responsible for judging your own work and only submitting answers that you know are correct. Generous partial credit will be given for problems that are correct, presented in finished form, but incomplete in that some parts were not done.