Are you referring to the fact that water is a compound while hydrogen is an element? If I'm wrong just comment and clarify and I can edit it, I don't even know what kind of unit you're in. :)
The visible spectrum is composed of red, orange,yellow, green, blue, violet, indigo.
<h3>What is visible spectrum?</h3>
The visible spectrum refers to the portion of the electromagnetic spectrum that can be seen with the eyes. All other portions of the electromagnetic spectrum are invisible.
The question is incomplete as the details are missing. The visible spectrum is composed of red, orange,yellow, green, blue, violet, indigo.
Learn more about the visble spectrum: brainly.com/question/1596783
Answer:
Wavelength of radio is wave is 3 m
Explanation:
Wavelength of radio is wave is

where

wavelength is

Multiplied by; speed = distance x time
Answer:
True.
Explanation:
According to Lenz's law, the induced current in a circuit always flows to oppose the external magnetic field through the circuit. This statement is true.
The Faraday's law of induction is given by :

Here, negative sign shows that the direction of induced emf is such that opposes the changing current that is its cause.
Hence, the statement is true.