What is the difference between the chemical bonds formed in molecules of O2 and the chemical bonds formed in crystals of NaCl?

Hen a gfci receptacle device is installed on a 20-ampere branch circuit (12 awg copper), what is the minimum volume allowance (in cubic inches) required for conductor fill for each conductor in the outlet box?

Ascientific blank must be testable and capable of being proven false?

This is the number of complete movements of a wave per second.