Proof always requires supporting material

A conversation with your friend would be different in a quiet library than it would in a crowded restaurant. These differences can be attributed to the changing _____ context

A) physical B) social-psychological C) temporal D) cultural

Lee de Forest:

a. manufactured crystal detectors that could capture radio waves. b. perfected a glass bulb called the Audion that could detect radio waves. c. conducted experiments that led to the first voice broadcast. d. started KDKA, the first commercial radio station.