OASDI stands for old age, survivor and disability insurance, which is more commonly referred to as Social Security. To pay for these programs, the federal government imposes a tax on earned income that must be withheld by your employer.
According to the December 1985 issue of Popular Mechanics, the Protex Safety Signal Company introduced flashing turn signals in 1920. The first modern turn signal, though, can be attributed to Edgar A. Walz, Jr. who, in 1925, secured a patent for one and tried to market it to major car manufacturers. They just weren't interested, and the patent expired fourteen years later. Meanwhile drivers and inventors kept working on other solutions.
The 100th anniversary of the first electric traffic light system will be marked on 5 August. It was installed on the corner of East 105th Street and Euclid Avenue in Cleveland, Ohio, and had red and green lights and a buzzer to provide a warning that the colours were about the change. Traffic signals' birth in London.