No need for cover sheet. Just around 300 words. APA format standards
When the results of a survey or poll are published, the sample size and the margin of error are both given. For example: 1000 voters were surveyed and 39±2% of the voters agree with the president. In this example N=1000 and the margin of error (MoE) is 2%.
This website lists several public opinion polls. Search the site and find a poll where the sample size and margin of error are given. Try to find a poll dealing with a topic in your profession or one in which you are really interested.