which of the following materials is found in some of the plastics used for computer cases?\ncopper\ndioxin\nl…

Answer:

None of the above options are typically found in the plastics used for computer cases. However, if we must choose from the given options, none of them are correct as plastics are polymers and these are inorganic substances or contaminants not integral to plastic - polymer structures. But if we consider in terms of possible contaminants or incorrect associations: Dioxin can be a by - product in some plastic manufacturing processes but is not a component of the plastic itself. Copper, lead, and beryllium oxide are metals or metal oxides and not part of plastic materials for computer cases.

Brief Explanations:

Plastics are organic polymers. Copper is a metal, lead is a heavy metal, beryllium oxide is an inorganic compound, and dioxin is a pollutant sometimes associated with industrial processes related to plastics but not a component of the plastic for computer cases.