Final answer:
The correct speed of light in air is approximately 3×108 m/s. It is a fundamental constant slightly less than that in a vacuum, and is vital in various physics calculations.
Step-by-step explanation:
The correct value for the speed of light in air is 3×108 m/s. The speed of light, denoted by c, is approximately 3.00 × 108 m/s in a vacuum and is only very slightly less in air due to the refractive index of air being very close to 1. This speed is a fundamental constant in physics and is used in various equations such as c = fλ, where f is the frequency and λ is the wavelength of the light.