Back in the days of 35mm film, a 50mm prime was considered a 'standard' lens. That's because it gives pretty much the same perspective as viewing a scene with the human eye, without the magnification of a telephoto lens or the shrinkage a wide-angle lens uses to squeeze more into the frame.
The flexi disc (also known as a phonosheet or Soundsheet, a trademark) is a phonograph record made of a thin, flexible vinyl sheet with a molded-in spiral stylus groove, and is designed to be playable on a normal phonograph turntable.
What is a Bulging Disc? Discs situated between the spinal vertebrae absorb shock and facilitate movement. Bulging discs, which typically surface in the lower back, occur when a weakened or deteriorated disc swells through a crevice in the spine, extending outside of its normal jurisdiction. This condition happens when a disc shifts out of its normal position, usually slowly and over a long period of time.