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.
Invention of traffic light . In 1923, Garrett Morgan patented his own version of traffic light. The Morgan traffic signal was a T-shaped pole unit that featured three hand-cranked positions: Stop, in all -directional stop position. This third position halted traffic in all directions to allow pedestrians to cross streets more safely.