White light is select one: a. light of wavelength 550 nm, in the middle of the visible spectrum. b. a mixture of all frequencies of visible light. c. a mixture of red, green, and blue light. d. the term used to describe very bright light. e. the opposite (or complementary color) of black light.

The correct answer is (b) a mixture of all frequencies of visible light.

The visible spectrum is in the range of 400 nm to 700 nm. when a white light is passes through a prism, it can be seen that white light is divide into 7 colour namely violet, indigo, blue, green, yellow, orange, and red, thus this can be conclude that the white light is a mixture of all frequencies of visible light.

your answer is c! hope this : )

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia