title: Visible spectrum
context: The visible spectrum is the portion of the electromagnetic spectrum that is visible to the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light. A typical human eye will respond to wavelengths from about 380 to 740 nanometers.[1] In terms of frequency, this corresponds to a band in the vicinity of 430–770 THz.
question: What is the frequency of light?
answers: 430–770 THz