A functional document, also known as functional specification, is a document that specifies the function that a system must perform, mostly regarded in systems engineering and software development. It typically describes what the system needs by the user, including the requested properties of inputs and outputs. It is somewhat similar to a matching requirements document.
Using steel in electrical wire has pros and cons it is and okey conductor but with no rubber tubing or even elrctrical tape around it .it will release energy and be wastefuli sugjest using alluminum alliods they have much better conductive powers.
Answer: from Greek photo-, combining form of phōs (genitive phōtos) "light" (from PIE root *bha- (1) "to shine").
Explanation: Please make brainliest