An accounting firm wants to know how many tax payers will wait until the last day to file their taxes. A group of 1000 tax filers were randomly surveyed, revealing that 100 of them said it was likely that they would not file until the last day. Based on this information, a 95% confidence statement indicated that the percentage of tax filers who would file on the last day was estimated to be between 8% and 12% of all tax filers. In this problem, which of the following is the margin of error?