If you are close to ovulation, EC may not be able to prevent pregnancy if you wait 5 days. Therefore, the best thing to do is take EC as soon as you can get it. A thorough and up-to-date academic review of the medical and social science literature on emergency contraception is available here .
Employer Identification Number - EIN. A unique identification number that is assigned to a business entity so that they can easily be identified by the Internal Revenue Service. The Employer Identification Number is commonly used by employers for the purpose of reporting taxes.
In the United States, a Social Security number (commonly known as SSN) is a number issued to U.S. citizens, permanent residents, and people that are temporarily working in the country. The number is issued to an individual by the Social Security Administration, an agency of the federal government.