The frequency of red light with a wavelength of 656 nm can be calculated using the formula: frequency = speed of light / wavelength. The speed of light is a constant value of approximately 3.00 x 10^8 meters per second. To convert the wavelength from nanometers (nm) to meters (m), we divide by 1 billion (1 nm = 1 x 10^-9 m). So, the wavelength of 656 nm is equal to 656 x 10^-9 meters. Now we can substitute the values into the formula: frequency = (3.00 x 10^8 m/s) / (656 x 10^-9 m) Simplifying this expression, we can divide the numerator and denominator by 10^-9: frequency = (3.00 x 10^8) / 656 Calculating this division, we find: frequency ≈ 4.573 x 10^14 Hz. Therefore, the frequency of red light with a wavelength of 656 nm is approximately 4.573 x 10^14 Hz.