What Is a Social Security Number (SSN)? A SSN is a nine-digit identifying number is in the format xxx-xx-xxxx. Any individual who is a U.S. Citizen, a permanent resident, or a temporary alien resident who is authorized to work in the United States, must have a SSN.
The most common cause of a flat tire is puncturing of the tire by a sharp object, such as a nail, letting air escape. Depending on the size of the puncture, the tire may deflate slowly or rapidly.
Dear Tom and Ray: Between yesterday afternoon and this morning, I have had three flat tires. The tire that was flat yesterday had a screw in it, and the tires that are flat this morning have finishing nails.