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.
Front wheels wrongly aligned cause uneven tyre wear and may seriously affect the car's handling. Toe-in or toe-out - the amount by which the wheels are closer or further apart at their front edges than at their rear edges - is adjustable on all cars.