An unused flashbulb contains magnesium and oxygen. After use, the contents are changed to magnesium oxide but the total mass does not change. This observation can best be explained by the.

Which of the following would be considered a nec code violation in regards to the installation of luminaires? a. an outdoor lighting fixture mounted to a tree b. a five-pound, 12-inch diameter light fixture supported by the screw shell of the lampholder c. florescent lay-in fixtures attached to the framing sections of a suspended ceiling with sheet-metal screws d. track lighting over a sink, 2 feet from a bathtub