Answer:
is the same for all waves regardless of wavelength
Explanation:
Electromagnetic waves are often collectively called light. Light has become a generic name that is applied to all electromagnetic waves. The arrangement of electromagnetic waves according to their respective wavelengths is called the electromagnetic spectrum.
When passing through a vacuum, all electromagnetic waves irrespective of their individual wavelengths must possess the same speed. This is called the speed of light in a vacuum. The speed of light in a given medium is a constant and applies to all electromagnetic waves irrespective of their frequency and wavelength.
