Question

the wavelength range of visible spectrum extends from violet (400nm) to red (750nm).express these wavelength in frequency

Answer 1

frequency = velocity/ wavelength

Answer 2

Answer:

An island or isle is any piece of subcontinental land that is surrounded by water.[1] Very small islands such as emergent land features on atolls can be called islets, skerries, cays or keys. An island in a river or a lake island may be called an eyot or ait, and a small island off the coast may be called a holm. Sedimentary islands in the Ganges delta are called chars. A grouping of geographically or geologically related islands, such as the Philippines, is referred to as an archipelago.